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SPIRALS
IN NATURE AND ART
A STUDY OF SPIRAL FORMATIONS BASED ON THE
MANUSCRIPTS OF LEONARDO DA VINCI, WITH
SPECIAL REFERENCE TO THE ARCHITECTURE
OF THE OPEN STAIRCASE AT BLOIS, IN TOURAINE,
NOW FOR THE FIRST TIME SHOWN TO BE
FROM HIS DESIGNS, BY THEODORE ANDREA
COOK, M.A., F.S.A., AUTHOR OF "OLD TOURAINE,"
"ROUEN," ETC., ETC., WITH A PREFACE BY PRO-
FESSOR E. RAY LANKESTER, F.R.S., ETC., DIRECTOR
OF THE BRITISH MUSEUM OF NATURAL HISTORY
WITH ILLUSTRATIONS
LONDON
JOHN MURRAY, ALBEMARLE STREET, W.
1903
76
Hfi
CONJUGI CARISSIMAE
PREFACE
I have often thought that if the public knew
more of the real beauties of Nature, our
Museums would be far more thronged with
visitors than is the case at present. Every
effort is made in many of them to display the.
various specimens to their best advantage, and
to explain clearly what they are. But some-
thing more is often needed, and the man who
knows most about these matters is not always
the man who has time to write about them.
Moreover, the writings of the specialist are too
often necessarily expressed in language that
is fully intelligible only to a few. Yet if the
energetic worker in other fields will pause a
while to consider what he can learn from
biology or botany, he will, I think, be rewarded
far beyond his expectations.
Leonardo da Vinci was one of the few men
x PREFACE
who can be great in several directions. His
painting would have sufficed alone, and by it
alone he is too often judged. But he was a
man of science, an engineer, a mathematician,
a biologist, as well ; and his leisure was given
to sculpture and to architecture.
Never has so much talent been united in one
man. Yet modern men of art and science,
who have specialised on their own subjects,
may derive great benefit from the work of
other specialists in these days when it is practi-
cally impossible to keep abreast of one line of
research without an exclusive devotion to its
progress.
As far as I am aware, Mr Theodore Cook
has not specially devoted himself to any of the
scientific subjects which come under the scope
of his present inquiry. He is perhaps known
to a few as the historian of some districts in
France. But his name is unfamiliar to
students of biology and mathematics. The
training which he received in Paris — a training
which I could wish were more appreciated at
our own Universities — has emboldened him to
enter upon a course of speculative generalisa-
tion which a more restricted method of study
might have prevented. He looks, in fact,
PREFACE xi
upon the results of others' labour with a mind
that is more ready to perceive its general value
than are those intellects which have concen-
trated a unique energy upon a single set of
problems.
I have perused with the greatest interest
many of those manuscripts of Leonardo on
which Mr Cook's work for this Essay has been
primarily based. I also know many of the
steps he has taken to arrive at his conclusions,
and among them I would point out the com-
parisons suggested in the growth of horns, as
shown in figs. 17, 18, 19 and 20 ; and the col-
lection of various shells, made to investigate
the growth of plaits upon the columella, as
seen in the series illustrated by figs. 52, 27, 30,
7, 53, 31, 32, and 33. These, it seems to me,
will be distinctly useful to the biologist, apart
from any connection in which they may be
found in these pages.
The hope that mathematicians may in time
produce a system of definitions that will be of
use both to the biological and to the artistic
morphologist, is by no means new. But every
fresh instance that tends to make it more
probable must contribute to the advantage
alike of science and of art. I am perhaps not so
xii PREFACE
much interested in the attribution of a certain
staircase to Leonardo as I am in the steps by
which Mr Cook seeks to enforce a theory that
is, after all, susceptible neither of proof nor of
disproof. Yet I feel that architecture, if it is
to appeal to all of us, as it should do, must, in
the end, be based upon some general morpho-
logical principles. I have long looked in vain
for any architectural hand-book that would not
merely suggest the foundations on which build-
ing and ornament finally rest, but would also
lucidly explain to the untechnical observer the
reasons, the faults, or the virtues of any archi-
tectural example with which he might be
brought in contact.
That there are certain natural laws which
bind the work of the architect as they must
bind the growth of all organic structure, is
evident. Mr Cook has suggested one of them,
and his suggestion involves, it seems to me,
a course of inquiry that would prove as service-
able to the builder as it should be fruitful to
the biologist.
The scientific reader will not need to be
warned against certain generalisations which
Mr Cook has formulated upon what are con-
fessedly insufficient data. But I am not aware
PREFACE xiii
that he has indicated anything that is in itself
improbable, or that may not be eventually
rendered possible when the scope of our experi-
ence and knowledge is enlarged by further
study. The investigation of spiral forms in
Nature is itself a department of scientific
inquiry that is still very incomplete, and I
believe I am correct in thinking that neither
in mathematics nor in architecture has the last
word yet been said upon this interesting
subject. There are many gaps in Mr Cook's
argument which may doubtless be filled up
by existing knowledge ; but there are many
more which await investigation, and he has at
least indicated one way in which their value
may be at once put to a practical test.
The example of Leonardo will be difficult
to follow until a man like Leonardo reappears.
Nature seems to have broken the mould, and
its fragments have been buried beneath com-
petitive examination papers. But when to a
creative imagination which approaches his,
shall be added a knowledge of Nature that
may well be greater, then every branch of
intellectual activity will benefit, even if the
immediate result be not all that Leonardo
hoped for when he wrote, so many centuries
xiv PREFACE
ago : " In this the eye surpasses Nature,
inasmuch as the works of Nature are finite,
while the things which can be accomplished
by the handiwork, at the command of the eye,
are infinite."
E. Ray Lankester.
CONTENTS
PAGE
Preface. By E. Ray Lankester . . vii
CHAPTER I
the argument.
Sympathy with, many things as essential as specialism
in a few — The secrets of Voluta vespertilio — Archi-
tectural theory — The Open Staircase at Blois — The
Manuscripts of Leonardo — The " Italian brother of
Faust " — Rodin's Creed — Discoveries of Leonardo 1
CHAPTER II
OF SPIRALS.
Right- and left-handed spirals — The Prentice's Pillar —
Columns at Canterbury — Screws and shavings —
Celtic torques — Left-handed men — Narwhal's tusks
— An Elephant's tusk — Helicoprion — Turbinella
rapa, the Indian Chank shell — Spiral ornament —
Helicteres ixora — Lanistes — A return to Nature . 26
xvi CONTENTS
CHAPTER III
OF PLANTS.
PAGE
"Lady's Tresses" — Pine cones — Palms — The Devil's
Corkscrews — Twining plants — Tendrils — Mr A. H.
Church and Phyllotaxis — The Logarithmic Spiral 54
CHAPTER IV
OF SHELLS.
Vorticella — Stentor — Dr George Wherry and the growth
of horns — Errors in argument — Spiral twists and
spiral curves — Bypaths of research— Spiral growth
in shells — Sinistral, dextral, and " ultra-dextral "
shells — Ammonite and Nautilus . . . . 73
CHAPTER V
COMPARISONS.
Scalaria scalaris and the Palazzo Contarini, Venice —
Wrong uses of spiral — Mitra papalis and Escalier de
la Heine Berth e, Chartres — Telescopium telescopium
and the old Staircase at Blois 94
CHAPTER VI
A VANISHED ART.
Constructive and deliberate " asymmetry "—Delicate
irregularities in line — Discovery of curves in
Egyptian and Greek Architecture — Evelyn in old
St Paul's — " Symmetrophobia " according to Pro-
fessor Goodyear — The Campanile at Pisa not
accidental — What we lose by mathematics . . 100
CONTENTS xvii
CHAPTER VII
THE NAUTILUS.
PAGE
Plaits on the columella of shells — Tracheae of insects
and spiral tubes in plants — A series, to show the
formation of the columella, from Turritella lenti-
ginosa to Voluta musica — Sir John Leslie, Canon
Moseley, and the Nautilus — Professor Goodsir and
the Logarithmic Spiral — M. Vial de Saint-Bel and
the race-horse " Eclipse "—Prof essor Weldon and
Clausilia laminata— Pasteur . . . . . 115
CHAPTER VIII
OF MASONRY.
Evolution of the spiral staircase in the Feudal Keep —
The steps that lead to Hell — Appearance of the
central shaft — Tower-houses and Newel-staircases —
A delicate problem in construction — The jest of
Chambord — Left- or Right-handed, " dexiotropic "
or "leiotropic?" 132
CHAPTER IX
THE EXILE.
Leonardo da Vinci at Amboise — Ludovico Sforza at
Loches, and Caesar Borgia at Chinon and Blois —
Clos-Luce — The grave at Amboise — Researches of
Leonardo — Botany — Architecture — Flight of birds
— Hydraulics — Head-dress for "Leda" — Shells —
The Amboise Stair and Turritella — The Blois Stair
and Telescopium 146
xviii CONTENTS
CHAPTER X
THE SHELL OF LEONARDO.
PAGE
The Open Staircase in the wing of Francis I. at Blois
— Its exterior and interior — Valuta vespertilio — Its
exterior and interior — Its rare and common forms
— Agreements and differences — The staircase a de-
liberate copy of the shell — The marvellous
construction and fine decoration of the staircase —
Why it is left-handed — Its date — Its architect was
left-handed — Advantages of the left-handed forma-
tion— The double spirals of Chambord built later
— Creative Imagination — The Search for Beauty —
The Logarithmic Spiral — The foundations of Taste
— The Ionic volute — " Majestati Naturae Par
Ingenium" 164
LIST OF ILLUSTRATIONS
FIG. PAGE
Amboise, from a Drawing by Leonardo da Vinci
(photogravure) .... Frontispiece
1. Voluta scalar is ...... 1
2. Solarium maximum . * . . .7
3. Example of a right-handed and of a left-handed spiral 26
4 The "Prentice's Pillar "at Rosslyn . . .29
5. Narwhal's tusks . . .To face page 41
6. Elephant's distorted Tusk . . „ 41
7. Turbinella pirum . . . . .44
8. Turbinella rapa . . . . . .44
9. Postage Stamp now used at Travancore . . 45
10. Helicteres ixora (Seed-Pod) . . ' .50
11. " Lady's Tresses " (Neottia spiralis) . To face page 55
12. Pine Cone ...... 54
13. Wax Palm— Date Palm .... 56
14. Pandanus utilis ...... 58
15. Case made by larvae of Caddis-fly (enlarged) . . 73
16. Capsule of Shark's Egg . .... 75
17. Bush-buck shot by W. Brodrick Cloete in South
Africa .... To face page 77
18. Tragelaphus angasi . . . ,^77
19. Spiral Twist : A. Angora— B. Markhor . . 80
20. Spiral Curve ; A. Highland Ram — B. Merino Ram
0. Alaskan Bighorn (Ovis nivicola) — D. Pamir
Sheep— E. Argali ..... 82
21. Spiral Staircase, Palazzo Contarini, Venice To face page 95
22. Scalaria scalaris ...... 95
23. Scala del Bovolo, Palazzo Contarini, Venice To face page 96
24. The Tower of Pisa ... 96
XX
LIST OF ILLUSTRATIONS
FIG.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
Wing of the
Escalier de la Keine Berthe, Chartres
Mitra papalis
Telescopium telescopium .
Staircase in the Old
Blois .
Geritheum giganteum
Voluta solandri .
Voluta pacifica .
Turbinella fusus .
Voluta musica .
Nautilus pompilius (section)
Logarithmic Spiral
Ammonites (arielites) obtusus,
Lyme Begis .
Argonauta argo .
Operculum of Turbo marmoratus
PAGE
To face page 97
. ' 97
98
Castle of
To face page 98
115
119
119
120
120
To face page 123
123
From the Lower Lias,
To face page 124
125
124
137
Primitive spiral staircase, with plan of one step
Elaborate spiral staircase with plan of improved
stonework . . . . . .142
Two floors of the CMteau of Chambord, showing the
interlacing spirals of the double staircase To face page 143
Central wooden shaft of the staircase in the College
de Montaigu . . . . . .144
Study for the " Leda," by Leonardo da Vinci, showing
spiral form of head-dress. (From the IVindsor
Collection) .... To face page 146
Study of the spirals formed by smoke and dust. By
Leonardo da Vinci (From the Windsor Collec-
tion) ..... To face page 152
Spiral motion of the tips of a bird's wings „ 154
Professor Marey's photographs of a flying pigeon, taken
at the rate of fifty a second. (From Pearson's
Magazine for May, 1902) . . To face page 154
A page of Leonardo's handwriting, from Leonardo's
Manuscript Note-book on the Flight of Birds. The
transcription of Giovanni Piumati and an English
version of the translation by Charles Ravaisson
Mollien .... To face page 155
LIST OF ILLUSTRATIONS xxi
FIG. PAGE
48. Study of the growth of flowers. By Leonardo da
Vinci. (From the Windsor Collection) To face page 156
49. A. and B. Study of the spirals formed in water. By
Leonardo da Vinci. (From the Windsor Collection)
To face page 157
50 Longitudinal section of intestine of Raia . .159
51. Turritella lentiginosa . . . . .159
52. Auricula auris-midm . . . . .159
53. The common form of Voluta vespertilio (section) . 165
54. Bare form of Voluta vespertilio (section) . .165
55. Escalier a Jour, Chateau de Blois, Touraine. The
Central Shaft . . . To face page 165
56. Common form of Voluta vespertilio . . .166
57. Bare form of Voluta vespertilio . . . .166
58. Escalier a Jour, Chateau de Blois, Touraine. The
exterior .... To face page 166
59. Vaulting and steps of spiral staircase in the wing of
Francois I., Chateau de Blois . To face page 170
60. A and B. Left-handed screws from Leonardo's MSS.
in the South Kensington Museum — C. (From the
Windsor Collection — D. Signature (from the Windsor
Collection) .... To face page 175
61. Method of describing the Ionic Volute by means of a
common whelk shell.
(1) Shows tape entirely wound round shell,
and pencil in position to start.
(2) Shows tape almost unwound, after nearly
completing its guidance of the pencil.
(3) Capital of an Ionic Column.
(4) Chrysodomus antiquus, the shell used to
describe the volute reproduced To face page 188
SPIRALS IN NATURE AND
ART
•-•- ~"~~ •■'•
L ......J!!,, ^„,.^„;- «.,- ■„* ** k.
Giovanni Bellini's Allegory of the Shell, painted for the owner of the "Staircase of the
Shell," in the Palazzo Contarini, Venice {see page 95).
[To face page 1.
CHAPTER I
THE ARGUMENT
" Ihr durchstudiert die gross' und kleine "Welt
Um es am Ende gehn zu lassen
Wie's Gott gefallt.
Vergebens, dass ihr ringsum wissenchaftlich schweift
Ein jeder lernt nur, was er lernen kann." x — Mephistopheles.
" II pittore deve essere universale." — Leon, da Vinci.
KOR the existence of an Essay
upon Spiral Formations in
Nature and Art, no better
apology can be offered
than the interest and beauty
of an inquiry which has
hitherto only been sug-
gested in a few scattered
Fig. i. pamphlets and disconnected
valuta scaiaris. references. But an excuse
is certainly needed for the fact that this
1 " "Pis best to study all things — everywhere —
Nature and man — the great world and the small,
Then leave them at haphazard still to fare,
It is, you see, plainly impossible
That one man should be skilled in every science,
Who learns the little that he can does well."
{From Goethe s Faustus.
Translated by John Anster.)
A X
2 THE ARGUMENT [chap.
inquiry was undertaken by one who knew
little history, less architecture, scarcely any
mathematics, and no morphology or botany
whatever. A deep knowledge of all five
seemed indispensable. But as the most
profound acquaintance with only one, or
even only two, was useless, I have ventured,
perhaps too boldly, to believe that to have
specialised in none, and to have the keenest
sympathy with each, is as good a qualification
for the task as may, for the moment, be
attained. My belief is all the easier because
it is accompanied by the confidence that every
specialist will delightedly correct those errors
which occur in ground familiar to him, while
he may perhaps be tempted — by their mere
proximity — to consider questions which he has
hitherto too often set aside as being beyond
his special province.
In either case I shall be sufficiently rewarded.
But I would not have it thought that I have
approached these matters lightly or suddenly.
They have been constantly in my mind for
thirteen years, and if I at length presume to
offer the result of my endeavours to the
public, it is because many of the questions
to which an intelligible reply is sought have
not yet been answered in any of the five
divisions of intellectual research already
mentioned, though distinguished exponents
i.] THE SPECIALIST 3
of each are firmly convinced that a reply
might be furnished by the others. It is in
the hope of eliciting such replies that these
tentative pages have been published. To
remain silent for lack of perfect detail in each
part, were but to strengthen the negative
gloom of the narrow specialist, whose motto
might well be the warning placed at the head
of this chapter, the lines that were spoken by
" The Spirit who Denies."
I do not give the names of many who have
offered me the kindest and most generous
assistance.1 They are all aware of my
gratitude ; and none of them might wish
to be made even remotely responsible for
suggestive generalisations that are unfettered
by too keen an appreciation of difficulties
in detail. Though I have been at great pains
to verify the facts here recorded, I will there-
fore beg that the architect will particularly
scrutinise my biological statements ; the
1 To helpers of a different kind I must express my
thanks by name, for without the careful drawings made
by Mr T. Green of Wallington, and the no less skilful
wood engravings of Mr Butterworth of Savoy House, my
argument would have entirely lost some of the most
convincing of its aids. The design of the twining hop-plant
on the binding, and the drawing of " Lady's Tresses " in
the text, are my mother's work. Messrs Sowerby and
Fulton of Kew have been of great assistance in choosing
some specimens of shells for me.
4 THE ARGUMENT [chap.
mathematician my excursions into art; and
that the historian will look indulgently upon
one result which seems to flow from
arguments based alternately upon both — a
result which, in the absence of all documents,
does not admit of perfect proof.
With this modest study in spiral formations
the great name of Leonardo da Vinci has
been connected on my title-page for reasons
that will soon become evident. But the
incident that first associated the two in my
own mind deserves recording, both as an
explanation of these pages and as an example
of scientific insight.
Just thirteen years ago I was dining at
Oxford, in company with some distinguished
biologists. Each seemed to have something
of value either to relate or to display, and the
unlearned guest was feeling a little at a loss for
any topic of discourse in a conversation which
ranged so far beyond his own experience and
knowledge. At length he ventured to
produce for general inspection a proof engrav-
ing upon Indian paper of a certain staircase
(see fig. 59), built by an architect whose name
has been hitherto unknown in the early
sixteenth century at Blois. I had but just
returned to Oxford after a long visit to the
banks of the Loire. I had endeavoured to
investigate the historical and artistic associa-
l] A DISCOVERY 5
tions of that wonderful valley for a book,1 to
whose publishers I felt deeply indebted for
thus bringing into greater prominence a
miracle of design which now seemed to
promise even greater fascinations than those
discovered in it already.
The little picture was indulgently received ;
and the joy of its humble possessor may be
imagined when one of the party loudly
proclaimed his recognition of the spiral curve
therein depicted. No sympathy was
suggested with any architectural problem;
but the critic who now held the picture of
the spiral staircase in his hand announced to
his comrades that the curves upon its central
column were identical with those of Voluta
vespertilio (see fig. 56).
Abashed, befogged, but keenly interested,
I hinted at my ignorance of what Voluta
might be. The shell was fetched. Still I
remained unmoved and unilluminated.
Finally the Professor had pity upon me. A
longitudinal incision was made, and the four-
fold spiral stood revealed within upon the
columella (see fig. 53).
Every one was soon talking of other
subjects, but I could think of nothing else.
In spite of many other conflicting interests
and duties I have thought of that chance
1 "Old Touraine" (Bivingtons, 1892).
6 THE ARGUMENT [chap.
discovery ever since. If a biologist could
recognise the lines that are hidden within a
certain shell as soon as he saw them repro-
duced in a French staircase, there was also
the possibility that the staircase had been
originally suggested by the shell. This idea
turned my thoughts to other spiral staircases
and other shells. I found that a Scala della
conchiglia and a Scala del bovolo (fig. 21)
were to be seen in Italy ; and that in the
Natural History Museum at South Kensington
there were a Voluta scalaris (fig. 1), a Solarium
maximum (fig. 2), even a Scalaria scalaris
(fig. 22). The connection between shells and
staircases was evidently present in the minds
both of those scientists who had bestowed
these names on shells,1 and of those persons
who had seen and admired a building
sufficiently to recognise the natural objects
it recalled. This by no means involved that
certain architectural forms could be explained
on a conchological basis, or that conchology
should ever be considered from an architec-
tural point of view. But it certainly did
suggest that a staircase whose form and
1 The name Voluta was given by Linnaeus. The species
Scalaris was described and named from the Barton Beds
(Middle Eocene) by J. de C. Sowerby in 1843. It may
be noted that fossils in these beds are wonderfully
preserved, even in colour, and include a very large
number of columellar spirals.
I.]
NAMES OF SHELLS
7
construction recalled a natural growth would
more probably be the work of a man to whom
Fig. 2.
Solarium maximum,
biology and architecture were equally familiar
than that of a builder of less wide attainments.
It would, in fact, be likely that the design had
8 THE ARGUMENT [chap.
come from some great artist and architect
who had studied Nature for the sake of his
art, and had deeply investigated the secrets
of the one in order to employ them as the
principles of the other.
It seems difficult for many architects,
when they commit their thoughts to paper,
to express their views moderately, so deep
are their personal convictions of what is right
and wrong. Some critics objected so vehe-
mently to one portion of these pages in their
earliest form * that they apparently refused to
consider any other.
As a matter of fact, I most thoroughly
accept the commonplace, that Art is one thing,
and Nature is another,2 and that mere un-
intelligent copying of natural phenomena
will never be artistic, however faithfully
performed. Structural forms in architecture
— it is as great a platitude as the other — are
usually the result of direct problems in
building. Yet I do not hesitate to say that
the philosophy of Architecture must finally
be based on general principles which will
appeal to other intelligences than those of
1 In The Monthly Review for April and May 1902.
2 "Nature," wrote Whistler, " contains the elements, in
colour and form, of all pictures, as the keyboard contains
the notes of the piano," but, " to say to the painter that
Nature is to be taken as she is, is to say to the player that
he may sit on the piano."
L] MATHEMATICS 9
the strictly professional architect. On the
other hand, though natural forms, unmodified
and unrestrained, can never become architec-
tural ornaments, yet it is not necessary to lose
all the charms of natural beauty by exaggerated
convention, or by too rigid application of the
square and the ruler. Indeed, I shall show
in later pages that it is only by appreciating
the irregularities of Nature that beauty can
ever be artificially attained (see p. 185).
Language is not literature ; nor is mere
verse poetry. Style is not attained by over-
elaborated exactness, nor is industrious
reproduction an attribute of genius. Architec-
ture should take her right place at the head of
all the Arts, because she can most clearly
manifest that divine attribute in man which
is connoted in Creation; and the creative
imagination is no more concerned with fancies
only than it is with facts alone ; it deals with
the material of scientific knowledge, and with
the causes that underlie phenomena, in order
to evolve new combinations of its own.
No one has yet been able to say who
designed the open staircase in the wing of
Francois I. at Blois, which is reproduced in
figs. 55, 58, and 59. If it were really the
conscious copy of a shell, the first step
towards a discovery of its designer would
be to find a man who lived near Blois between
10 THE ARGUMENT [chap.
1515 and 1520, who was a friend of Francois
L, who was something more than a mere
master-mason, and who was likely to have
studied shells not merely as a biologist, not
merely as an artist, but also as a scientist
and a philosopher, who was in search of those
hidden natural causes which might be applied
to the products of human handiwork. To
all these somewhat general qualifications there
is but one man who can justly lay claim —
Leonardo da Vinci, that great Italian artist,
mathematician, scientist, and engineer, who
died in exile within a few miles of this very
staircase a year or two after it had been
begun.
The main impression produced by this
building is its spiral formation. It is there-
fore likely that its builder would have given
particular attention to spiral formations in
Nature, with the object of discovering the
principles involved in them. I shall hope
to show that this was one of the many
problems to which Leonardo turned his extra-
ordinarily original and acquisitive intellect ;
and in the various instances of natural spirals
which I have collected I would also point
out that the original indication was given
me, in almost every case, in his manuscript
notes. These manuscripts suggest many
problems which even the present advanced
i.] LEONARDO'S MANUSCRIPTS 11
state of scientific knowledge is unable as yet
to answer; and therefore my original voyage
of discovery in search of the designer of a
particular staircase has led me, by natural and
unavoidable paths, into an inquiry which
ranges far beyond either the building or its
builder, and leads towards those ultimate
principles of construction and of growth which
Leonardo did so much to discover, and which
his successors are still endeavouring to grasp.
Though less than a dozen undisputed examples
of Leonardo's paintings exist, it is chiefly
as a painter that he is known to general
fame. The bulk of his sketches and manu-
scripts in this country exceeds by many times
the whole of those possessed by other nations,
yet the value and contents of these do not
seem to be so well appreciated in England
as they are elsewhere. They have been
investigated by Venturi, Libri, Govi, Kichter,
Ravaisson-Mollien, Beltrami, Miintz, Miiller-
Walde, Uzielli, Sabachnikoff (fig. 47), Piumati,
Duval, Seailles, and the editors of the facsimile
edition of the Milan manuscripts, to name no
more. Apart from the actual drawings and
studies they contain, these manuscripts are very
much like the notes that might be made by an
exceptional Professor for a course of very extra-
ordinary lectures. They display a gift of literary
expression and construction which lags very
12 THE ARGUMENT [chap.
far behind the ardour for discovery that in-
spired them. For this reason their writer
remained almost unheard by his con-
temporaries, and is scarcely yet appreciated
by his posterity. His arguments are not
presented in that logical form which helps a
reader to understand their drift. His discus-
sion of the connection between the Scriptural
Deluge and the fossil shells found upon a
mountain-top is one of the few cases in which
the literary form of the inquiry is complete.
It is therefore only natural that the isolation
of his own intellectual life should have been
almost reproduced in the comparative neglect
of his manuscripts in later years. It was one
of his favourite sayings that the strength of
the painter was in solitude : — " Se tu sarai
solo, tu sarai tutto tuo."
Another drawback is the material one of the
difficulty in deciphering his writing. Whether
it be true or not that it was owing to travels in
the East that he took to writing from right
to left, it is certain that he largely employed
a caligraphy which can best be read in a
mirror (see fig. 47), and which was also an
easy accomplishment for a left-handed man.1
1 A landscape drawing in the Uffizi — the authenticity of
which has never been called in question— is dated " The
day of S. Mary of the Snow, the 5th day of August, 1473,"
when Leonardo was just twenty-one ; and Mr M 'Curdy has
L] LEFT-HANDED 13
If the shading of his drawings had not
revealed the peculiarity, we should have known
that Leonardo was left-handed from the
statement of his friend Fra Luca Pacioli, for
whose book, "De Divina Proportioned' he
designed the figures.
These are some of the reasons why the
secrets of a man who spent the last years of
his life in exile at the beginning of the
sixteenth century remained his own until
the last years of the nineteenth. Yet his
fame is only strengthened by that long
oblivion. For the laws which he established
or divined have been independently discovered
and proved as advancing knowledge made
researches easier ; and the reputation of his
successors remains untarnished ; for though
their discoveries must now be antedated by
three or four centuries, they made them in
their turn while Leonardo's manuscripts were
still unknown. A sower of ideas of which
he never saw the harvest, he jealously guarded
them from intrusion during his lifetime, and
they never came to light till long after his
death.
pointed out that this inscription shows Leonardo had
already adopted the method of writing from right to left ;
so that I prefer the theory that this was the natural method
of the left-handed man, rather than the acquired result of
any possible travels in the East,
14 THE ARGUMENT [chap.
Before me as I write are some five hundred
careful photographs of the originals existing in
England, to which it may be hoped that a fuller
justice will some day be done than I can now
find to be the case. Though it was necessary
to examine all of them, only a very small
fraction bore upon the special subject of this
work, and only a very few examples have been
chosen out of these to indicate the kind of
material available (see figs. 43, 44, 47, 49), and
to produce the barest essentials in the progress
of this argument.1 They embrace drawings of
landscape and figures, which are evidently
studies for pictures ; anatomical drawings of
great beauty and skill ; botanical sketches,
architectural plans, biological notes, numerous
engineering problems, many mathematical
inquiries, the whole dashed down without much
order, in a very fervour of investigation.2
Carrying as he did, in that brain which
1 I have also examined the MSS. in Paris, Venice,
and Milan, where the numbering of the great "Codice
Atlantico" has been corrected by the Abb6 Ceriani, and
the whole is being reproduced at the cost of the State.
2 Though many pages that have survived cannot, under
any hypothesis, be considered as prepared for publication,
there is some evidence in others that Leonardo not only
wrote for a public, but was conscious of his literary short-
comings. "Blame me not, 0 reader," he says, for instance,
in one note-book, "for the subjects are numberless, and
my memory is weak, and I write at long intervals. ..."
L] RESEARCH 15
bore so many images of beauty, not only all
the science known at the beginning of the
sixteenth century, but almost half of the
attainments that the years since then have
brought us, Leonardo lived of necessity a
lonely life ; and with advancing years it is
known that his thoughts turned more and more
from painting to problems of natural science,
and to vast collections of natural objects. His
quest was that of Goethe's Faust : —
" Das ich erkenne, was die Welt
Im innersten zusammenhalt
Schau' alle Wirkenskraft und Samen
Und thu nicht mehr in Worten Kramen." x
It was a characteristic of his genius that
the patent phenomena of life did not content
him. He insisted on going deeper. "Ma
tu che vivi di sogni" he writes in the
Treatise on Flying (fig. 47), " ti piace pin le
ragion soffistiche e barerie de palari nelle cose
grande e incerte, che delle certe, naturali, e
non di tanti altura" 2 His intellect was as
1 " 0 for a glance into the earth !
To see below its dark foundations
Life's embryo seeds before their birth. ..."
(Goethe s Faustus, trans, by John Anster.)
2 "But thou who livest in dreams art more pleased
even with the sophistical reasonings and theories of
philanderers, when they deal with great and unknown matters,
than with researches into things certain, natural, and
of a lower interest."
16 THE ARGUMENT [chap.
sincere as it was sagacious. He penetrated
the secret hiding-places of truth with a
passionate industry that never shrank from
toil. " Truth/' he cries,1 " is so excellent that
by her praise the very smallest things attain
nobility." His method was that of Darwin,
proceeding by an analysis which does not
fear to be diffuse; grouping isolated pieces
of evidence, attaining at last a final law, or
at least a hypothesis that would explain the
facts. His anatomical drawings, apart from
their exquisite draughtsmanship, contain so
many keen parallels and suggestive indica-
tions that the author of the " Origin of
Species" would have perused them with
delight.2 It is perhaps a loss both to Science
and to Art that the majority of Leonardo's
manuscripts do not seem to have been known,
as far as we are aware, either to Darwin or to
Ruskin.
I shall have occasion to mention several
instances of Leonardo's use of that experi-
1 The passage begins as follows: "Ed 5 di tanto
vilipendio la bugia, che s'ella dicessi be'gran cose di dio,
ella to' di grazia a sua deit& ; ed 6 di tanta eccellenzia la
veritk . . ."
2 In the manuscripts at Windsor, for example, there are
careful drawings to show that the tail in other animals
existed in a modified form in man. Huxley's manuscript
memoranda are, I am informed, full of delicate drawings,
and in other ways somewhat similar to those of Leonardo,
ij IMAGINATION VI
mental method which Humboldt recom-
mended and Galileo used. He understood
to the full the definition of Science as "the
knowledge of Causes "—Tore eirurrd[i€0a 6W rrjv
airlav ctSw/Acv. He realised even more keenly the
necessity that Science should be largely oc-
cupied with speculations, with hypotheses,
with imaginations, with what Miiller in 1834
called " Phantasie." 1 Nature must be inter-
rogated in such a manner that the answer
is implicit in the question. The observer can
only observe when his search is guided by
the thread of a hypothesis. It is the thread
of spiral formations that has guided these
chapters. It was the manuscripts of Leon-
ardo which inspired them.
The laborious collection of facts alone is
powerless if it does not go further. The
imagination, unrestricted, can neither con-
vince nor gratify. But in combination the
1 "Die Phantasie ist ein unentbehrliches Gut; denn sie
ist es, durch welche neue Combinationen zur Veranlassung
wichtiger Entdeckungen gemacht werden. Die Kraft der
Unterscheidung des isolirenden Verstandes, sowohl als die
der erweiternden und zum Allgemeinen strebenden Phan-
tasie sind dem Naturforscher in einem harmonischen
Wechselwirken nothwendig. Durch Storung dieses Gleich-
gewichts wird der Naturforscher von der Phantasie zu
Traumereien hingerissen, wahrend diese Gabe den talent-
vollen Naturforscher von hinreichender Verstandesstarke
zu den wichtigsten Entdeckungen fiihrt." — Joh. Muller,
Arch, fur Anat. 1834.
B
18 THE ARGUMENT [chap.
two can do what, for w^ant of a better word,
we call " create."
This was Leonardo's meaning when he said
that " the works of Nature are finite." They
move along those orderly, those vast, processes
of time and space which can be realised by
that human intelligence which is a part of
them, if only it will work hard enough to
collect the details.
" Ich stand am Thor ; ihr solltet schliissel sein ;
Zwar euer Bart ist kraus, doch hebt ihr nicht die Riegel.
Geheimnissvoll am lichten Tag
Lasst sich Natur des Schleiers nicht berauben
Und was sie deinem Geist nicht offenbaren mag,
Das zwingst du ihr nicht ab mit Hebeln und mit
Schrauben." 1
This, then, is to " know " ; but to " create "
is greater, for creation takes that further step
which is beyond knowledge, yet must ever
be based on knowledge ; and this is the truth
which the great Italian expressed in that hard
saying of the eye surpassing Nature ; for he
realised that " the things which eye and hand
1 " I stand before the guarded door
Of Nature, but it bids defiance
To latch or ward : in vain I prove
Your powers — the strong bolts will not move.
Mysterious in the blaze of day-
Nature pursues her tranquil way. . . ."
(Goethe's Faustus, trans, by John Anster.)
i.] THE ITALIAN FAUST 19
can create are infinite." "AH things are
artificial/' said Sir Thomas Browne, "for
Nature is the art of God."
Michelet described Leonardo, in a tho-
roughly characteristic phrase, as "the Italian
brother of Faust " ; but there is an even closer
parallel between the Italian and Faust's great
creator, Goethe. For the genius of the
German shone not merely in the poetry and
prose of which he is the acknowledged master,
but in osteology, in botany, in morphology,
in anatomy, in optics, in the theory of archi-
tecture. His name will indeed be connected
with some of these as long as it is honoured
in the language he immortalised. Like
Leonardo, Goethe projected a mind that was
primarily artistic into all those scientific
problems which the errors or inadequacy ot
his time had left incomplete. Such prophetic
insight as was theirs is never understood in
the age of which it is a part. But when
their day has itself become a portion of the
past, then their own value emerges clear, in
its true perspective, above the many-headed
ignorance that once shrouded them ; for "it is
not the intelligent man, but Intelligence, that
rules." "There is no such thing," cried
Goethe, "as a patriotic art." Like all else
that is great and good and true, Art and
Science belong to the whole world. It is
20 THE ARGUMENT [chap.
only by constant reference to our great in-
heritance, and by a constant interchange
of ideas between every contemporary worker,
that we can advance at all. This, therefore,
is another reason why I have ventured to
ask the architect to consider the biologist
in a kindlier light, and invited the mathe-
matician and the botanist to lie down together.
It is only by such intercommunication as
modern inventions and modern tolerance
have rendered possible that any of us can
ever approach that large point of view which,
in the case of Leonardo, was possible to a
single man. " La Nature" said Rodin, " cest
le rnodele variable et infini qui contient tous
les styles. JElle nous entoure, mais nous ne
la voyons pas" The ideal of the sculptor
speaking at the dawn of the twentieth century
was that of the artist working in the fifteenth.
As has been finely said of the Frenchman,
he knew "all there is to know of the apti-
tude of clay to receive, of marble to declare,
his own intimate interpretation of those large
secrets of the Universe which escape the
narrow definitions of logic and of language/'1
But Leonardo went further than this ; for
he possessed to an extraordinary degree that
masterful quality of the human mind which
Goethe called " das Damonische," that power
1 Rt. Hon. George Wyndham, 15th May 1902.
i.] SCIENTIFIC WORK 21
which makes and transforms ideas, that living
and constructive energy which flings itself into
the future wrhile it assimilates the present.
" Ich, mehr als Cherub, dessen freie Kraft
Schon (lurch die Adern der Natur zu fliessen. . . ." 1
It must be remembered, too, that Leonardo
lived and laboured in an age when what we
may call "the scientific sense" was far less
developed than it is now, and when the
multitudinous possibilities of the printing
press, the camera, and the telegraph were
either unknown or unappreciated. In his
library, biology was represented by Pliny,
John de Manderville, and "a lapidarium."
Yet he suggested the theory of the eye,
which was slowly elaborated from Leonardo
to Kepler, from Kepler to Helmholtz.
" II Moto," he wrote, " e causa d'ogni vita."
"Activity," said Professor Clifford four
hundred years afterwards, "is the first con-
dition of development." Leonardo was the
first to propose a division of animals into
vertebrates and invertebrates. He guessed
that the blood circulated, but could not
explain the mechanism. "The heart," he
1 "High above cherubs — above all that serve
Raised up immeasurably — every nerve
Of Nature's life seemed animate with mine. . . .'
(Goethe's Faustus, trans, by John Anster.)
22 THE ARGUMENT [chap.
wrote, "is a muscle of great strength . . .
the blood which returns when the heart
opens again is not the same as that which
closes the valves."
Long before Bernard Palissy he studied the
fossil shells on mountain tops, and showed
that "the Deluge had nothing to do with
them," and that they were remains of living
organisms, left there by water, "Nature's
Charioteer," in the course of prolonged
changes in the surface of the earth, and
revealing in their fossil state the circum-
stances of their far-off existence. He thought
that "the sandy desert beyond Mount
Atlas" had formerly been "covered with
water," and anticipated Cuvier by showing
that the level of the sea's bottom is con-
tinually rising, sometimes rapidly, sometimes
by lengthy accumulations of debris, and
pointed out the strata in the stone of the
Apennines revealed by the cutting of the
river Lamona. He gave as long as two
hundred thousand years for the accumula-
tions formed by the river Po ; and in geology
his investigations directly foreshadow in other
ways the work of Lyell, who established
geology as a science by showing that the
causes which had produced the past were
still at work producing the future, just as
Darwin not only explained the biology of
l] PHYSICAL DISCOVERIES 23
vanished forms, but gave the reasons for
further development, and assigned living
things to their right place in the great order
of Nature.
Besides founding the study of anatomy
Leonardo was the first to investigate the
structural classification of plants, and (in the
fourth book of the " Trattato " ) to study the
system on which leaves are disposed and
arranged about their stalks, and laid down
laws which were re-discovered independently
in the seventeenth century. He explained the
suspension of bodies in the air, and
experimented on the consistency of the
atmosphere at various heights, besides going
far towards a solution of those problems of
flying which still occupy us to-day. " II sole
non si move/' he wrote, anticipating
Copernicus in propounding his theory of
the movement of the earth round the sun,
and explaining to the dogmatists of his day
that " the supreme, wisdom of God 1 guided
him to choose those laws of movement which
were in closest agreement with abstract
and metaphysical reasoning."
He laid the foundations for those laws
of the movement and equilibrium of fluids
1 Compare the " Digression of the Wisdom of God in the
Site and Motion of the Sun " in Sir Thomas Browne's
" Vulgar Errors," VI. v.
24 THE ARGUMENT [chap.
which were completed by Pascal, D'Alembert,
Bernouilli, and others. He proved that water
in communicating vessels remained at the same
height in each, which was the theory of the
hydraulic press of 1653. Attracted irresistibly
by the practical problems of the Scriptural
" Deluge/5 he covered innumerable sheets
with studies of the movement of water under
the stress of such a sudden cataclysm. The
canals and irrigating works already existing
in Lombardy were enormously improved by
his hydraulic knowledge, and his contrivances
were still employed by the Milanese at the
end of the seventeenth century. He ex-
perimented on the lines which subsequently
produced the " camera obseura," and
initiated the theory of complementary
colours which was carried on by Chevreuil.
Of his numberless mechanical inventions,
it will be sufficient to say that he designed a
breech-loading cannon which propelled its ball
by steam, that he invented paddle-wheels for
boats, and that he suggested the use of
parachutes and of screws turning on a vertical
axis as a means of aerial locomotion. Other
details will appear in their right place, when I
come to point out more emphatically those
investigations into spiral forms in Leonardo's
manuscripts which are especially appropriate
to the subject of this book. But I have said
i.] STUDIES IN NATURE 25
enough already to remove any improbability
from the suggestion that as an architect
Leonardo would be likely to show traces of
his studies in other directions, and I can now
pass on to consider more closely the form
and meaning of various kinds of spirals.
Besides collecting and examining some
spiral formations in Nature, with the object
of discovering, if possible, any principles
that may underlie their existence and con-
struction, I shall call attention to those
formations in Art which may appear to be
more particularly connected with this
subject; and it will thus be possible to
realise a little better the full value and
meaning of the architectural example with
which this book concludes. The attribution
of a certain staircase to a certain master may
not interest many beyond a restricted class
of readers ; but the steps by which that
attribution is arrived at, and the artistic
principles of which that staircase is a type,
are matters that should appeal to the far
larger audience to whom questions of taste
and of abstract beauty are not limited by the
requirements of a single profession or a single
branch of knowledge.
CHAPTER II
OF SPIRALS
what
"Search where, thou wilt and let thy Reason go
To ransome Truth even to th' Abyss below ;
Rally the scattered Causes, and that line
Which Nature twists, be able to untwine."
T3EFORE me as I write is a plain
. cylinder of wood, nine inches high,
with a diameter of just over one
inch (fig. 3). I have taken a piece
of string eighteen inches long and
nailed it to the bottom edge, in
order to wind it round the cylinder
to the top edge. In doing this, I
find it easier and more natural to
make the first turn of the string
towards the right, with the result
that the three visible lines of the
string made by its ascent upon the
cylinder are all curves which move
upwards towards the right, and
these curves are in the form of
is called a spiral, and sometimes a helix.
chap.il] RIGHT-HANDED FENCING 27
When I rotate the cylinder on its axis they
remain the same. In this instance I have
formed a right-handed (or dextral) cylindrical
spiral (see fig. 27). When a watch-spring lies
flat upon the table it forms a plain spiral (see
figs. 34, 85). If you fix its largest circle to
the table, and raise up its innermost point,
you find that a conical spiral has been formed ;
and a good natural example of this is shown
in Mitra papalis (fig. 26). •
At the same point on the bottom edge of
the cylinder where I had fixed my string,
I now fix a piece of flat narrow tape of
precisely the same length, so that I can
wind it round the cylinder to the same point
on the top edge reached by the string. I
had naturally wound to the right before,
because my right hand (being that of a right-
handed man) always finds it easier to make
a circle towards the right than towards the
left, just as every right-handed fencer knows
that the contre-sixte is an easier parry than the
contre-quarte, because the circular movement
of the hand is towards the right, whereas1
1 In driving, the instinctive movement of the hand
would turn a horse to the right when passing an obstacle
in its way, and most nations are content that this should
be so, although the coachman's seat is placed over the
right wheel. The English, however, have logically over-
come their instincts and drive to the left ; they prefer to
see where their right wheel is going.
28 OF SPIRALS [chap.
Kirchhoffer, a left-handed man, is celebrated
for his contre-quarte.
I now begin by turning my tape to the
left, and when it is fixed at the top, I
find its three ascending curves go up by a
different and symmetrically opposite path to
that taken by the string; I have made, in
fact, a cylindrical spiral, which is not of the
usual dextral or right-handed form, but
sinistral or left-handed. The difference seems
very simple when it is expressed in simple
language, but it will have to be kept very
carefully in mind in the course of these pages,
for a good deal will be found to depend
upon it. So much, indeed, is this the case,
that I find it impossible to proceed without
placing my cylinder upright on the table
before me, with the two different threads of
string and tape clearly showing the difference
between the two forms of spiral ; and I notice
it does not matter which end of the cylinder is
at the top, for the spirals remain the same if
I stand it upside down ; and this may also be
prettily demonstrated by reversing this book
and looking at the staircases shown in figs.
28, 55 and 59, from the top instead of from
the bottom, a point of view which will indeed
only emphasise the complicated beauty of
their construction.
The beautiful effect obtained in wrhat is
II.]
NATURAL BUILDING
29
known as the " Prentice's Pillar," in Rosslyn
Chapel (fig. 4) is due
to the fact that its
separate right - handed
spirals (proceeding from
their separate points)
envelop in their long
and slender ascending
curves a pillar which
is artfully grooved in
perpendicular lines, so
that full value may be
given to the encircling
decoration. In Nature
the ascending curves of
spiral growth are nearly
always, like these, to-
wards the right, as
shown by the Pillar
and by the string upon
my cylinder, when ob-
served at right angles
to its elevation. Either
very rarely in a " sport,"
or with some definite
reason in artificial ex-
amples, the ascending
curves are those towards F,G' 4'
the left, as Shown by ^ Up-ntice'sPillar"atEosslya.
the tape when its course is followed from the
SO OF SPIRALS [chap.
bottom ot the cylinder upwards. Such
reverse curves a right-handed man makes
with conscious effort either with his right
hand or right foot ; they seem in fact to
be chiefly connected with descent, and may
be observed, under certain circumstances, in
the fall of a strong stream of water from a
height. We should not expect them, there-
fore, to occur in architecture, because man
builds upwards, and his upward spiral
movement would be instinctively to the right
as it is in the " Prentice's Pillar."
In the Chapel of the Holy Innocents in the
Crypt of Canterbury Cathedral (beneath St
Andrew's Chapel) there is a short column, with
a shaft four feet in height, showing spiral bands
running upwards to the right with very fine
effect ; and it is curious that the same crypt
provides an interesting example (in St Gabriels
Chapel, beneath St Anselm's Tower) of a
column with a shaft five feet in height, which
begins with a left-handed spiral in its grooved
decorations, but, half way up, these grooves are
changed to a right-handed spiral, with a band
of irregular incised diamonds to mark the
transition, as if the workman had felt that the
design had been begun wrongly, and had there-
fore corrected its direction. This was built in
1103, and in 1121 a further development in
spiral decoration is observable in the same
il] CANTERBURY CRYPT 31
building. If you stand in front of the Lady
Chapel in St Ernulf 's Crypt, and look west-
wards down the central alley, you will see eight
pairs of columns, of which the second, fourth,
sixth, and last exhibit a spiral arrangement of
grooves. In the first two a right-handed spiral
is elaborately decorated throughout. In the
next pair, the bands of decorations are cut
alternately in right-handed and left-handed
spirals, and end in straight fluted grooves.
The left-handed arrangement is never per-
mitted to stand alone ; from which we may
perhaps infer, that if there was one left-handed
man among the masons, his right-handed
comrades took care that he should never com-
plete a design which did not fall in with their
idea of what was appropriate to the principles
of growth, support, or strength, typified by a
column (see p. 96).
The commonest instance of a cylindrical
spiral is the homely corkscrew, which may
be placed for comparison beside our cylinder
of tape and string, and it will be seen that
its masculine strength of penetration is ex-
pressed by the same right-handed curves as
those of the string.1 If you place it upright
1 I need hardly perhaps remind the traveller that he
would never have got across the Rocky Mountains in a
railway train if the track had not been planned on a
feasible gradient by the scheme of spiral tunnels gradually
ascending like a corkscrew.
32 OF SPIRALS [chap.
upon its point, you will observe that an insect
ascending to the handle would be perpetually
turning to the left, so conchologists call this
spiral " leiotropic," for they seem to have
connected shells and staircases together as
soon as scientific terminology became common.
If you imagine that the string surrounding
our cylinder is made of the same substance
as the cylinder, and projects a little further
from the surface, you will have an example
of the ordinary screw. The coffin-screw, on
the other hand, is that fortunately rarer
variety which only penetrates when it is
turned in the unusual direction, to the left.
In these military days it is also possible to
point to a sinistral spiral which has become
a common object of admiration, and that is
the rifling in a Lee-Metford, which is made
to turn to the left in order to counteract
the pull of the average right-handed soldier.
It is curious that all left-handed spirals look
as if they were at almost double the pitch
of the corresponding right-handed spirals ;
perhaps because they are less familiar to the
eye.
A screw may be defined as a cylinder of
wood or metal having a spiral ridge ( " the
thread " ) winding round it, usually turning
in a hollow cylinder, in which a spiral channel
is cut corresponding to the ridge. The
ii.] SHAVINGS S3
distance between the medial lines of any two
successive threads of a screw, measured in a
direction parallel to the axis, is called "the
pitch " of the screw. A " screwstone " is the
name sometimes given to one of the joints
of the stem of an encrinite, or " stone-lily,"
a Palaeozoic crinoid plentifully found in
marble, and belonging to a class of animals
(echinodermata) which are stalked, or fixed
like a plant for some or all of their lives. A
" Portland screw " is a similar name bestowed
on the fossil cast of the interior of Cerithium
Portlandicum. The name of "Augur-shell"
has for the same reason been given to a
toxoglossate gastropod called Terebra (Bullia)
semiplicata, and more especially to T.
maculata.
As we shall see when we come to consider
the origin of spiral shells, the force which
determines the original direction may be very
slight and subtle, yet is invariably "good
evidence." The shape of the shavings at a
carpenter's bench, for instance, might furnish
another Sherlock Holmes with the proof he
required that his murderous mechanic was
either left-handed or a Japanese ; for one of
these two he must have been if the shavings
exhibit a sinistral spiral. The right-handed
screw which is usual in the innocent shaving
is produced because the right-handed carpenter
34 OF SPIRALS [chap.
invariably drives his plane a little to the left.
Orientals seem always to prefer a left-handed
spiral, just as they write from right to left,
and a common example may be found in those
silver-headed walking-sticks of blackwood
which, in all instances I know, are carved in
left-handed spirals, where a Western workman
would naturally have turned them to the
right.1
Many of the walking-sticks sold to our
officers in South Africa, and made by Zulus,
are carved into a sinistral spiral, but it is
impossible for me to say whether this is owing
to left-handed workmanship, or to imitation
of a climbing plant which coils (like our own
hop) in a left-handed spiral. I was at first
inclined to think that the persistence of the left-
handed twist in prehistoric Irish torques, as
may be seen from examples from Dublin, and
in the British Museum, was due either to the
predominance of left-handedness in Ireland,
which is shown by the use of the light left-
hand axe mentioned by Giraldus Cambrensis,
or to the fact that the most skilful artificers
were developed from left-handed men. But
nothing is so strange about spiral formations
as the results of practical experience, and I
1 An interesting comparison may be found in the spiral
twist which forms so common an ornament in Swedish
silver spoons.
il] TORQUES 35
soon found that the flat ribbon of soft gold
from which the earliest torques are made,
would naturally become a left-handed spiral if
twisted by a right-handed man, for he would
hold down one end with his left hand, and
would twist the other end outwards with his
right hand, with the result that the spiral of
the twisted gold would be left-handed, as may
be proved by any one with a long piece of
narrow paper. This may account for the fact,
that from the many torques I have examined,
all the gold examples were left-handed, the
only right-handed spiral shown being a silver
specimen in the Germania Museum at Nurem-
berg, and another silver specimen now in the
Society of Antiquaries. The five-coiled arm-
let in the British Museum, exhibits the usual
left-handed twist, but has the additional charm
of showing four distinct spirals, which has
resulted from the use of four flat ribbons
of gold united, the combined section being
cruciform before the process of twisting had
begun.
The use of this spiral formation as an
honourable ornament is certainly as old as the
golden collar promised by Belshazzar as a
reward, the Chaldee name for which was
Meneka, transliterated in the Septuagint (Dan.
v. 7), as Maytag. From the Chaldseans this
form passed to the Persians, and the mosaic
36 OF SPIRALS [chap
pavement from Pompeii, now in the Naples
Museum, represents Darius and his officers at
the battle of Arbela, wearing torques which
end not in the usual cones, but in snakes'
heads. The crest of the Manlius family in
Rome had its origin in the prowess of T.
Manlius Torquatus, who beat a Gaul in single
combat, and took from him the torque which
had descended to his nation as an honourable
symbol from Chaldsean sources, and which
passed on to Druids and Celts in the British
Islands in the various forms that are now
discovered in their tombs. The collar itself
(though not its spiral form) continues to be a
mark of honour to the present time, among
Knights of the Garter, or the Golden Fleece,
and even among provincial Mayors. Indeed,
the phrase " Collar-day," as an ordinary con-
comitant of courtly ceremonial, is to be
found in almost any issue of the Lord
Chamberlain's instructions for " red-letter "
days, when there are special Collects, Epistles,
and Gospels said in Church, and when the
judges wear red in the Courts. The only
difference between the modern insignia of rank
and the Celtic torque, is the loss of the signi-
ficance involved in the spiral form of the
primitive decoration.
The Investigations of the Anthropological
Society of Washington (May 1879) go to
il] LEFT-HANDED MEN 37
show that though left-handed workmen
existed in the Palaeolithic Age, prehistoric man
was as a rule right-handed. The buttons of
our own dress, like the hooks and eyes of our
ladies' attire, are now expressly adapted to the
right hand. So are the adze, the plane, the
gimlet, the cutting end of the augur, the
scythe, the fittings of a rifle, scissors, snuffers,
shears, and other mechanical tools which must
be used by one hand or the other ; or, when
used by several men at once, must be used by
the same hand in each man. All this, how-
ever, will not prevent one who is naturally left-
handed from continuing his natural practice,
though it is attended by great mechanical
inconvenience in all the instances mentioned.
A man with only a slight bias towards his
left hand will readily become ambidextrous
owing to the many right-handed conventions
and appliances which occur in everyday life.
But the instinctively and strongly left-handed
will never change, and is usually distinguished
for his skill, as Sir Daniel Wilson has pointed
out in his interesting monograph on the
subject. When Gideon discomfited the hosts
of the Amalekites, the seven hundred Ben-
jamites he selected for their superior skill
in slinging were all left-handed.1 Only the
1 Compare the chapter on " The Right and Left Hand/'
in Sir Thomas Browne's "Vulgar Errors/' IV. v.
38 OF SPIRALS [chap.
best, in fact, of the left-handed men can
survive in the struggle against the vast
majority of right-handed influences around
them, and their skill will go on increasing, as
may be seen in the case of left-handed fencers
who have far more opportunity of practising
against right-handed men than we have of
getting used to them.
It is worth noticing in this connection that
when Londoners had an opportunity, in
March 1902, of seeing eight of the best fencers
in the world, of whom four Italians were pitted
against four Frenchmen, the pair who did
best of all were the two famous French left-
handers, Louis Merignac and Kirchhoffer.
Indeed, instead of starting at a disadvantage,
as is too often assumed, a left-handed artist
has generally the advantage of his right-
handed rivals, for he is usually ambidextrous
by education, besides being possessed of
a high degree of congenital skill in the
hand he prefers, as may be seen in the
instance of Leonardo da Vinci or of Hans
Holbein.
It is probable that when it was not a matter
of importance for a helix to be either dextral
or sinistral, the first sketch for such a helix
made by a left-handed man would more often
exhibit a sinistral than a dextral spiral ; but
when we come to an example of a sinistral
ii.] NARWHALS 39
helix which may have been designed by
Leonardo da Vinci, I do not, therefore, wish
to argue that his skill in drawing with his left
hand was alone responsible for the rarer
formation. The fact that he was left-handed
may certainly have suggested the original
form of the left-handed helix which he eventu-
ally elaborated for other — and more potent —
reasons.
Dr Wherry has pointed out that right-
handedness or left - handedness sometimes
leave definitely traceable effects in the works
of early or unskilled artists. In the archaic
bust of an Apollo forty-seven curls out of
sixty-one turned the way of the clock-hands.
In another statue, dating before the Persian
war, the curls are arranged in right- or left-
handed spirals, according to the side of the
head on which they grow, not as in Nature.
I have mentioned the slight causes which
may give an apparently accidental origin to a
spiral. The follicle of hair is a good example
of this. In Western peoples it is generally
straight, but in the negroid races the follicle
is bent, and the result is the spiral shown in
curly hair. The socket of a tusk or the base of
a horn has much the same effect on growth.
The two examples of narwhal's tusk (really his
front tooth), which I have chosen from the
Museum of the Royal College of Surgeons
40 OF SPIRALS [chap.
(fig. 5), show excellently the rare sinistral
spiral, and the variation shown by the
additional curves in one of them is no doubt
due to a slight variation in the socket.
Every narwhal tusk I have ever seen (and
there are six now in one naturalist's shop in
Oxford Street) has a left-handed spiral, in-
cluding a sixteenth century carved specimen,
now in the Sala dei Stucchi of the Doges'
Palace, and another still older tusk, preserved
in St Mark's Treasure, in Venice. But they
exhibit an even more extraordinary partiality
to this formation. There are seven examples
known of narwhals with a double tusk.
One of these is in the British Museum
of Natural History at South Kensington.
Instead of following the examples of the horns
I mention later (p. 80), and showing differ-
ent spirals, this pair of tusks exhibits two
spirals of the same kind, and each of them
is sinistral ; and though I only speak of what
I have myself examined, the statement has
been made that whenever a narwhal has two
teeth their spirals are identical, instead of
exhibiting symmetrically different spirals
about the middle plane of the body, as might
have been expected. Dr Wherry thinks that
as an unerupted tusk exhibits a perfectly
straight fibre, the direction of the spiral
is formed after it leaves the bone and
-' -
Fig. 5.
Narwhal's tusks.
Fig. 6.
Elephant's distorted Tusk.
[To face page 41.
ii] PHARAOHS SERPENTS 41
becomes opposed to the waves during growth,
owing to the fact that the creature "plays"
to one side as it ploughs through the water ;
and when by a rare chance two tusks are
developed, the creature preserves the habit
of carrying its head on one side and so
gives both tusks the sinistral twist it gives to
one. In the Museum of the Royal College of
Surgeons I found an elephant's tusk (fig. 6)
which exhibits a very abnormal form indeed,
for, instead of being the usual segment of a
circle, the tusk has grown into a sinistral
spiral, so much accentuated by causes latent
in the socket that the whole thing has taken
a complete corkscrew formation.1 That an
alteration in the socket is quite sufficient to
control the formation of a growing spiral may
be proved by placing one of the eggs called
" Pharaoh's serpents " in a small tube. As
soon as the spiral begins to come out of the
egg it will exhibit a dextral helix if the tube
is dented slightly on the left, and a sinistral
helix when the orifice of the tube has a dent
upon the right.
Another example of the spiral arrangement
in teeth is so curious that it must be inserted
1 Frank Buckland had certain rabbits' teeth in his
collection which had grown into a spiral form owing to an
injury at their base from a stray shot or some other
accident.
42 OF SPIRALS [chap.
here. In the Imperial School of Mines at
St Petersburg is a fossil which has been given
the misleading name of Helicoprion. A cast
of it is placed among the fossils at the British
Museum in South Kensington. In general
shape it very much recalls the form of the
section of the Ammonite shown in fig. 366,
but a closer examination shows that it is really
a row of sharp teeth set upon a ribbon which
is spirally constricted into that form. On the
drawing of the logarithmic spiral in fig. 35,
1 have placed letters that will explain the
growth of this queer fossil, which has now
been proved to be a single transverse row of
teeth from the jaw of an Elasmobranch fish.
The new growth comes from the point A ;
the teeth are used for biting at the point B ;
and as they become worn out they move back
in a spiral direction, the small teeth of the
young fish being naturally in the centre of
that spiral at C, and the larger teeth of the
growing fish being at A.
An analogous case of this strange folding-up
of disused teeth is to be found in Cochliodus
contortus, a shark-like fish from the carboni-
ferous limestone, with crushing teeth instead
of the pointed teeth of Helicoprion; and a
very similar arrangement of growTth may be
observed in the teeth of the Skate, which grow
at A, are used at B, and, after beginning a
ii.] RARE FORMS 43
spiral curve, fall away before reaching any-
where near the point C — a much more con-
venient arrangement, it would seem, than
that of carrying disused teeth coiled up some-
where in the head, as must have been the case
with Helicoprion.
The difference between such dextral and
sinistral spirals as we have now seen artificially
constructed, "from the outside," will become
more and more suggestive when we investigate
a few examples of spiral growth " from with-
in " in plants and other natural objects ; and
we shall find that when objects which usually
display a dextral helix are found to show a
sinistral helix, some peculiar value and often
some supernatural signification is attached to
them by the primitive races who make the
first discovery. The delight in such rarities
of Nature, and the instinctive use of them as
ornament, was shown by Schliemann to be at
least as old as ancient Troy ; for he found that
an inland people had used the echinus or sea-
urchin as a model for the bosses which they
set round the circle of their shields.
A still more interesting example, which
has left easily verifiable traces at the present
time, is the belief of the inhabitants of
Travancore that the sacred shell called
" Sankho " is a manifestation of the god Vishnu,
because its internal spiral does not turn to the
44
OF SPIRALS
[chap.
right (with its " entrance " therefore also to the
right), as in the case of the
shell Turbinella pirum (fig.
7), and in a million other
examples, but turns to the
left (with its "entrance"
also to the left) as in Tur-
binella rapa (see fig. 8) with
the rare sinistral helix ; and
this belief survives in the
drawing, conventionalised
though it be, of this sacred
fig. 7. shell (with its opening to
TurUneiia pirum. the left) which is to be seen
upon the postage stamps
now used in Travancore
(see fig. 9). This Turbinella
rapa, called the " chank
shell/' is represented in
Hindoo religious art as held
in the hand of Vishnu. It
is fished for at Tuticorin on
the Gulf of Manaar from
October to May, and in
1887 a good sinistral speci-
men found at Jaffna was
sold for Rs.700. Nearly all
the shells brought up are
sent to Dacca to be sliced into bangles and
anklets for Hindoo women ; and this use of
Fig. 8.
Turbinella rapa.
II.]
USEFUL SHELLS
45
shells as ornaments among savage inland
races, and more civilised dwellers by the sea,
may be paralleled in every quarter of the
globe in the earliest periods of time. In the
Indian Ocean Cypraea moneta (the " money-
cowry") has for ages been employed as a
medium of exchange, as is Cypraea annulus
in the Pacific. In Bengal in 1854, the value
of 5,120 cowries came to one rupee. In
Egypt the same shell is still
considered to be a preservative
against the "evil eye."
The use of the spiral in
ornament goes back to pre-
historic times in other in-
stances. In the work of the
Bronze Age flat spirals are
found hanging to the side of
a shield as decorations, just
as on an ancient Pile- Hut- Urn (which is
mentioned in Sir John Lubbock's "Pre-
historic Times," and is thought to come
from Melos) the walls of the house are
represented as being decorated with large
spirals ; and Mr Arthur Evans found a frieze
of spirals and rosettes painted on the walls
of the Palace of Minos at Knossos in
Crete. From the well-known fact that the
mediaeval monks used to say their prayers
within a maze, to escape the pursuit of the
Fig. 9.
Postage Stamp now used
at Travancore.
46 OF SPIRALS [chap.
Devil, the spirals tattooed upon a Maori's
face may have the same object of confusing
the Evil One, though it may quite as possibly
be a result of his inborn sense of the adapta-
tion of ornament to form ; for his spirals
admirably express the feature decorated, and
seem to do so in a way which concentric
circles never can. Spirals are found in the
decorative art of such different peoples as the
natives of New Guinea (especially where
Melanesian influence occurs), of Borneo, of
ancient Peru, of Central Africa. Sometimes
the form is connected with the manufacture of
pottery or basketwork, and it is then definitely
suggested by the structural lines of the object.
Often the spiral seems the genuine expression
of artistic feeling or fanciful imagination. But
in no case do we find a savage making an
abstract pattern that does not go back to
Nature by a series of conventional variations.
All forms of the spiral in Polynesia, for
instance, can be traced to a Malay centre, and
that centre took its ornaments from Hindoo
or Phoenician sources.
No doubt the discovery of bronze was a
most substantial step in the progress of
civilization, inasmuch as this discovery en-
abled the men of the Stone Age in Northern
Europe to learn such patterns as the chevron,
the meander, and the spiral scroll, at the same
ii] THE LOTUS 47
time as they learnt the arts of metal-working.
Patterns grow : they are not made. They
are evolved from pictures, and from those
pictures which most often occur, and are most
easily repeated. Among such pictures, those
which represented the lotus would be as
significant and as sacred as any known to the
earliest periods of Egyptian art. The earliest
pictures were not done for their own sake, as
" works of art." They were meant to convey
an idea; they were even supposed to retain
some of the powers and qualities of the
original. So the lotus, as the emblem not
of one god but of all, not of one sacred
animal but of all, embodied an enormous
amount of ancient and popular symbolism,
and supplied patterns to paleolithic peoples,
whose pictures we know to have been life-like
representations of the incidents of the chase.
Spiral scrolls have been found on pottery in
Schliemann's " First Tomb " at Mycenae ; on
scarabs of an Egyptian dynasty which existed
three thousand nine hundred years before
Christ ; on bronze axe-heads from pre-historic
Sweden. Mr Henry Balfour possesses many
examples in the Pitt Rivers Museum at
Oxford. At Leyden the representative ex-
hibit for the Malay Archipelago is unique. The
ethnographic collections in Washington, in
Rome, and Amsterdam, are also full of similar
48 OF SPIRALS [chap.
specimens. Throughout, the theory of
spontaneous generation falls to the ground.
The rule of historic development and tradition
shows no exception ; and Professor W. H.
Goodyear has very carefully investigated the
whole subject as suggested to him first by
the geometric lotuses upon the Cypriot vases.
He showed that all the Arab and
Mohammedan spirals came from the
Byzantine Greeks ; that they are not found
at all in barbaric Africa, and that, on the
other hand, they are the foundation of Malay
ornament ; they reached Alaska, however,
by means of Buddhist influence, along the
Amory valley, through the Yakoots to the
Aleutian islands. When it is realised that five-
sixths of the ornamental patterns of ancient
Egyptian art were based upon the lotus and
its spiral derivatives, the number of spiral
traditions which spread from the Nile valley
all over the world will be better understood.
The oldest forms of the spiral associated with
the lotus are found in Egyptian tomb-ceilings.
The Greeks and Assyrians, who found the
flower already conventionalised almost out of
knowledge, took the spiral accompaniments
and developed them in turn to their highest
pitch. The Assyrian idea of the organic
connection of repeated units of design by
linked curves, ending in spiral volutes, was
il] FOLKLORE 49
immeasurably improved by the genius of the
Greeks, which seized on elements of beauty
that had hitherto remained unproductive, and
gave them not merely new life, but measure-
less scope.
I have thought it well thus early to suggest
that the widespread value attached to the
spiral formation as a decorative pattern has
been very largely owing to the fact of its
origin, and of its association with the lotus,
the symbol of creative power or energy, of the
strength and divinity of the sun, of the
sun's birth from moisture, and of the many
sacred phenomena of life. The lotus was used
for the first time in the decoration of the
English throne in Westminster Abbey in
1902 ; and it will be seen in later pages that
modern research has largely justified a
symbolism which was based rather on faith
than knowledge (see p. 189).
But we have found that escape from danger,
as well as ascent into new being, has been
associated with the spiral ; and one of the
most delightful forms in which the idea occurs,
has been told me by Mr George Calderon,
whose knowledge of the folk-lore and magic
of Eastern Europe seems as inexhaustible as it
is interesting. It appears that at the baptism
of a Lithuanian infant the parents bury one of
its little curls at the bottom of a Hop-pole, so
D
50 OF SPIRALS [chap.
that the child may " twine out of danger " in
its lifetime, just as the spiral tendrils of the
plant twine upwards to the light. Another
strange fancy is the use to which the spirally
twisted seed-pods of Helicteres ixora have been
put by certain races, who assumed (by the
" doctrine of signatures ") that their peculiar,
shape (see fig. 10) would make them an
admirable medicine for " twisted bowels," or
colic. It was similarly believed
that the plant called " Jew's
Ear" was a good remedy for
earache.
It is quite possible, therefore,
that the sinistral spiral for many
Fio. 10. ages had a deep signification as a
Helicteres ixora symbol, and that any specimens
(Seed-Pod)
in shells known (for example)
in the early sixteenth century would be
brought home, if possible, by travellers, and
valued by collectors, for this extraneous
reason, quite apart from the biological prob-
lem they present. The four great columns
set up behind the High Altar in St Mark's at
Venice, are all carved in left-handed spirals;
and some special value connected with that
formation is suggested by the tradition that
they originally came from the Temple of
Solomon in Jerusalem. The same spiral was
carved on the pillar of St Bernwand at
.
il] SINISTRAL SHELLS 51
Hildesheim in 1022. I think, too, that any-
one who had ever studied the laws of organic
structure would be particularly attracted by
shells. The " Allegory" painted by John
Bellini (in the Academy at Venice), may well
indicate that shells were as full of legend and
interest in his time as they are to-day, when
greater knowledge has only brought the
certainty of far more complex causes.
There are some divergences in "natural"
spirals which are inexplicable on the theory
that one kind is normal and the other very
rare. On the beach at Felixstowe, for
instance, you may pick up specimens of shells
which exhibit dextral and sinistral curves
in about equal proportions ; but after a little
investigation it appears that all those with
the sinistral curve have fallen out of the cliffs,
and are in fact the fossil Fusus antiquus of
the Red Crag Sea; while modern whelks of
the same kind in the North Sea apparently all
possess the dextral curve. The spiral horns of
fossil animals, however, do not differ from those
of living creatures. Near Lake Tanganyika
there is an amphibious mollusc with a large
shell, called Lanistes, which in that locality
always exhibits a spiral of the left-handed
formation. The same shell when it is found
at Lake Nyassa or the Victoria Nyanza,
exhibits a dextral helix. Is this difference
52 OF SPIRALS [chap.
connected with the fact that, as the recent
Biological Expedition seems to show, Lake
Tanganyika has had some past connection
with the ocean, whereas the others are fresh-
water lakes ? 1 There is another strange beast
within its waters which exhibits one kind
of spiral externally, and another internally,
but it still awaits a more precise examina-
tion.
The development of microscopical and
photographical research has put before our
designers many beautiful forms in Nature
which older workmen never knew. In such
organisms as Hexacoralla, the diatoms, the
calcispongise, and snow-crystals, the most
exquisite combinations are to be found, which
should alone be sufficient to inspire a new
school of design in ornament ; and though I am
here chiefly concerned rather with structure
than with decoration, these examples are all
germane to the general principle of this Essay,
which aims, in the humblest manner, at
suggesting a return to Nature by our crafts-
men, fortified as they now are by the enormous
advances in scientific knowledge since the
days when the old workmen drew their
inspiration from the things they saw. In the
Past, men worked well because they worked
1 See "The Tanganyika Problem," just published by
J. E, S. Moore. (Hurst & Blackett.)
_
il] THE GOTHIC SPIRIT 58
in one style. Now the majority of our
architects copy bits from every previous style,
and lose all originality. The best style of the
thirteenth century, for instance, may be
almost entirely explained by that illuminating
flash of light in which men saw the true
proportions of Nature, the unsurpassable
beauty in the structure of her forests, the
moulding of her flowers, the living grace
of her animals and plants. We know far
more to-day. Will it not be worth while
to try if we cannot create something for
ourselves a little better ?
CHAPTER III
OF PLANTS
As woodbine weds the plant within her reach,
Rough elm, or smooth-grained ash, or glossy beech,
In spiral rings ascends the trunk and lays
Her golden tassels on the leafy sprays.' '
TN plants many particularly
beautiful examples of
spiral formations and
growth are to be found,
and it will not be for-
gotten in this connection
that the structural classi-
fication of plants owes as
much to the researches
of Leonardo da Vinci as
does the science of
anatomy; and it is not
generally known that
Leonardo also carefully
studied in the fourth
book of the "Trattato" the system on
which leaves are disposed and arranged
about their stalks, long before Bonnet's
54
Fig. 12.
Pine Cone.
Fig. 11.
"Lady's Tresses" [Neottia spiralis.)
[To face page 55.
chap, in] AN ORCHID 55
"Spiral Theory" (to which I shall refer later
on) had been published in 1754. One of
his many beautiful drawings of botanical
subjects from the Windsor Collection is
reproduced in fig. 48. He was especially
fond of the many exquisite spiral lines ex-
hibited in the growth of the Cyclamen.
Since his day the subject has been investi-
gated by many great observers, and the mere
facts of spiral growth would take too long
to enumerate here.
A very peculiar effect is observable in the
growth of an Orchid, called " Lady's Tresses "
{Neottia spiralis), found for me in North
Devonshire. It is not a climbing plant at
all, yet its buds are arranged to catch the
light in an exquisite spiral of the rare
sinistral form, which can almost be seen to
move as the plant stands by a window in a
glass of water. The drawing in fig. 11
was an exceedingly difficult piece of work,
so often did the plant slightly alter its
surfaces during the hour it was being closely
studied.
In the cone of Pinus smithiana (fig. 12),
the spiral arrangement of the overlapping leaves
is very distinct. The economy of space ensured
at the points of growth is as observable as
the curious manner in which each of these
leaves is enabled, by its special relation to
56
OF PLANTS
[chap.
its neighbours, to obtain the maximum of
light with the minimum of shade. In this
instance, it should be noted that the true
growth is a right-handed spiral. In this cone
the lines of a left-handed spiral (in which
the beginning of each line is on the left,
and the lowest point on the right) may also
be observed, but in them it will be seen that
Wax Palm.
Fig. 13.
Date Palm.
the scales are intersected by other scales from
the row above, whereas in the true spirals
the scales grow round and round, overlapping
each other, but never interfered with by a
scale from a different line.
In Museum No. 2 at the Royal Botanical
Gardens, Kew, is a section of the trunk of
the Carnauba Palm from Brazil, sometimes
called the Wax Palm (Copemicia cerifera),
m.] SCREW PALMS 57
which shows very clearly the left-handed
spiral exhibited in the example of the same
tree in the British Museum of Natural
History, drawn in fig. 13. But there is
another example of this same Wax Palm in the
same room at Kew, which is no less clearly
arranged as a right-handed spiral. The Date
Palm {Phoenix dactylifera), also shown in fig.
13, was drawn from an example in the Museum
at South Kensington, and shows a right-
handed spiral ; but in Museum No. 3 at Kew,
the same tree exhibits a left-handed spiral.
If the common Chestnut Tree be carefully
compared to the Horse Chestnut, it will be
seen that the spiral growth of the bark on
their straight stems is set in different ways.
Of all the plants I examined at Kew, the
various kinds of Pandanus in the large Palm
House afforded the most beautiful instances of
this remarkable form, and their growth is
extraordinarily like that of a spiral staircase.
But here, again, we get the same puzzling
divergencies. Pandanus vandermeschii, a
maritime variety of this " screw-palm " from
Madagascar, is arranged in a right-handed
spiral, as is Pandanus utilis (fig. 14). But
the left-handed spiral is found both in
Pandanus sylvestris, from the Isle of Bourbon,
and in Pandanus millore, from the Nicobar
Islands. The plant called " Rata," which
m
OF PLANTS
[chap.
climbs up the New Zealand Gum-Tree, is an
example of another kind of spiral growth.
A visit to Kew Gardens will reveal many
Fig. 14.
Pandanus utilis.
more instances of the same formation. In
the flower of the white Water-Lily the various
organs will be found to be arranged in a
m] CONVOLVULUS 59
continuous spiral, and the Egyptians, noticing
a similar formation in the Onion, often used
that plant to typify eternity. In all the
more primitive flowers a spiral formation is
exhibited, as opposed to the concentric circles
in the "floral diagrams" of more highly
developed species. This spiral arrangement
also seems to me to be not only nearer to
primitive Nature, but also more beautiful
and suggestive ; for the spiral begins in the
centre with the carpels, and the various organs
in the course of their growth gradually slide
out of one formation into another, until they
become the sepals on the outside, which are
often green and leaf-like.
The bud of the Convolvulus closes and opens
with a spiral twist, and it may be noted that
the Byzantine builders of St Mark's were
peculiarly fond of the beautiful lines of the
Water-Lily and the Convolvulus flowers, as
motives for the decoration of their columns ;
not, perhaps, taking these forms consciously,
but producing the same effects by the careful
modelling and the artistic proportions of their
convex and concave capitals. In all ordinary
Yews the leaflets grow opposite each other,
but there is now a variety in which the
leaflets are set in a spiral, and the name
by which they are distinguished is a record
of the fact that all were grown from a
60 OF PLANTS [chap.
single "sport" which occurred at Florence
Court.
Some very extraordinary spiral fossils, found
in the Bad lands of Nebraska, have only just
had attention drawn to them by the scientific
world ; and by the kindness of Dr W. H.
Drummond, of Montreal, a specimen will, it
is hoped, soon be placed in the British Museum
at South Kensington. Their exact origin and
nature are still the subject of discussion, but
as the balance of expert opinion inclines to the
belief that they are not only organic, but also
plants, I have inserted what is known about
them in the present chapter.
Professor Erwin Hinckley Barbour has
published an illustrated description of many
examples of these "Devil's Corkscrews" or
"Fossil Twisters," called in more scientific
terminology, Dcemonelix, which he found in
large quantities at Eagle Crag, on Pine Ridge,
near Harrison, in Sioux County, Nebraska.
These peculiar structures, as anomalous as
they are unique, are found over an area of
some 400 square miles, between the White
River and the Niobrara River, and to a depth
of about 200 feet. They are corkscrew-shaped
columns of quartz, sometimes embedded in
sandstone, sometimes "weathered out" quite
clear of the original matrix. The spiral varies
in length, but sometimes is as much as twenty
in.] D^MONELIX 61
feet long, and perfectly regular throughout.
At the lower end is a large transverse attach-
ment, not spiral but smooth, and roughly
cylindrical in shape, as large round as a hogs-
head, and longer than the spiral growth above
it. The surface of these spiral fossils is a
tangle of ramifying, intertwining tubules
about an eighth of an inch in diameter, which
thicken inside into a solid compact wall
showing (under the microscope) plant tissue
arranged in fibres. Every microscopic section,
without exception, shows unmistakable plant
structure.
An immense lake of fresh water, in long
distant periods of time, once covered the great
basin east of the Rocky Mountains, of which
the sand-rock of the modern district, all sedi-
mentary and of aqueous origin, is a relic. In
the course of ages this lake became filled up
by detritus poured in from the rivers, and its
water-plants were buried in sand. By degrees
these plants decayed, and, particle by particle,
were replaced by silica, the material of quartz ;
and in this manner the huge corkscrews of
quartz now found on Pine Ridge have pre-
served the shape, the spiral growth, and the
huge roots, of the vast water- weeds which
flourished long ago at the bottom of the lake,
and persisted in growing at various levels, one
above the other, as the filling-up process went
62 OF PLANTS [chap.
on, until at last the lake became dry land, and
its weeds vanished — to reappear as Dcemonelix.
The spirals are both right-handed and left-
handed, and their symmetrical arrangement
round a vertical axis is alone sufficient proof
that they are not the remains of any animal or
of any animal's abode.
Other strange hypotheses have been put
forward to explain these odd formations ; but
this is not the place to enlarge upon them ;
for the theory that they are the fossil stalks of
giant water- weeds, explains all the facts as
known at present; and though the skeletons
of animals have in two cases been found in
connection with them, I cannot believe that
Dcemonelix was ever a rabbit-burrow.
The phenomena of climbing plants are
among the most interesting of all spiral
developments in Nature ; the subject of their
right- and left-handed spirality is now being
investigated, I believe, by Francis Darwin,
who should produce some very valuable
results. In most observed instances, the Hop
and the Honeysuckle twine to the left, but the
majority of twining plants exhibit a right-
handed screw, contrary to the sun, as in the
case of the French Bean, the Convolvulus, the
Pea tribe, and the Passion-flower. Charles
Darwin once examined seventeen plants of
Loasa aurantiaca, and found that eight showed
in.] NUTATION 63
the dextral formation, five preferred the
sinistral, and four reversed their spiral after
a part of their growth had taken place in
one direction. Plants became climbers, he
thought, in order to expose their leaf-surfaces
to as much action of light and air as possible,
and to do this with the least possible ex-
penditure of organic matter. The facts
observable in their growth certainly make
it very difficult to accept the phrase "the
power of movement" as a differentiation
between animals and plants.
In examining those plants which twine
spirally round a support, Charles Darwin
found that in two hours and eight minutes the
shoot of a Hop made one complete revolution
to the left with the sun, and that the tip
of a 31 -inch shoot of Ceropegia Gardnerii
made a circular movement to the right at the
rate of 33 inches an hour, contrary to the
sun, in search of an object round which to
twine. Every part of such a revolving shoot
in a twining-plant has its own separate and
independent movement, described by Sachs
as "revolving nutation," a movement which
appears to be due to the more rapid growth of
cells on one aspect or edge than on the other,
which makes a curve in the shoot, and rotates
it, as the growth alters and alternates. The
result of this is that when a revolving shoot
64 OF PLANTS [chap.
meets with a support, its motion is arrested at
the point of contact, but the free projecting
part goes on revolving. As this continues,
higher and higher points are brought into
contact with the support and there arrested,
and thus the shoot winds round, just as a
swinging rope which hits a stick coils round
the stick in the direction of the swing.
" Irritability " has nothing therefore to do
with these phenomena. The shoot twines
round its support rather more slowly than
it would revolve by itself (the difference
being about 1^ to 1), owing to the con-
tinued disturbance of force by arrestment at
various points. But when the shoot has made
its first, close, firm spiral, it slips up the
support in more open spirals, because it is freed
from the pull of gravity. " The majority of
twining plants," says Dr Wherry ( " On Spiral
Growth," 1898), "are no longer able to climb
actively, if their support forms a smaller angle
with the horizon than forty -five degrees ; and
the influence due to gravitation is such that if
the pot containing a plant which twines round
a rod is inverted, so that the twining apex is
lowermost, the youngest coils of the shoot will
loosen themselves, the free terminal bud will
erect itself, and will again grow upwards close
to the rod."
After carefully investigating the growth of
m.] HOPS 65
Hops up a straight meshed- wire fence, set up
round a Berkshire tennis-lawn, I found one
example of the twining apex having got lower-
most, owing to some interference by the
gardener during the growth of the plant. In
the course of the next twenty-four hours the
free terminal bud had erected itself again,
turned upwards, and twined to the left up its
own pendent shoot, taking three spiral twists
completely round, before allowing the new
extremity to grope freely in the air after a
fresh support.1 In this instance, there was not
only the spiral curve to be observed, but also a
very clearly marked spiral growth in the fibre
of the plant itself, which, in four out of five
observed cases, was strongly sinistral. In the
fifth case it was nearly straight, but whenever
any inclination was observable, it was to the
right. The reason for this exception I was
not able to discover. Indeed, the whole
question of torsions in the true axis of a spiral
twist revealed a serious complication for so
unskilled an observer as myself. Fortunately,
however, a reference to Charles Darwin's ex-
periments showed that the axis is twisted, in
all cases, owing to the roughness of the usual
natural support, and the rough, glutinous
1 This hop-branch was the model for the conventional
design (by J. E. Cook) of the binding on the back of this
book.
£
66 OF PLANTS [chap.
surface of my Hop- shoot is a good example of
this. He even trained some Kidney-beans up
a smooth glass rod, to prove that they scarcely
showed any twisting at all. No doubt the
twist provides an additional strengthening of
the fibre, which enables the plant to surmount
inequalities, and the spiral twist (as opposed to
the spiral curve) in the horns of goats and
antelopes, and on the columella of certain
shells, may be an evidence of a similarly
necessary strengthening process.
A different class of climbing plants is that
which possesses " irritable" organs, such as
tendrils, which clasp any object they touch.
These can grow horizontally, or up and down,
in distinction to those twining plants which
can only coil themselves round and climb up
supports that are almost upright. Whereas
these latter always go round a stick in the
direction of their own revolving movement of
growth (which may be either to the right or
the left, as we have seen), tendrils can curl
indifferently to either side, according to the
position of the supporting stick, and the side
first touched, the clasping movement of their
extremity being undulatory or vermicular.
The tendrils of all tendril-bearing plants
contract spirally after they have caught an
object — with about four exceptions, of which
Smilax aspera is one ; and this contraction,
iil] BRYONY 67
says Charles Darwin, is quite independent of
that power of spontaneously revolving which
is observable (by " nutation " ) in the apex
both of the shoot and the tendril ; for
Ampelopsis hederacea does not thus revolve
at all. The use of the spiral contraction of
a tendril is to drag up the shoot by the
shortest course towards the object clasped
without any waste of growth. This same
spiral contraction also makes the tendrils
highly elastic, and therefore stronger to resist
the wind, so that the Bryony, for example,
will outride a storm like a ship with two
anchors and a long range of cable that serves
as a spring.
In the Bryony a filiform organ grows out
from the plant, as Dr Wherry observed, and be-
comes " irritable " in such a fashion that, while
revolving at its free end exactly, as if groping
for a prop, when this free end touches a twig,
it coils round it at once. The coiling tendril
then develops a corkscrew spiral twist in one
direction in one part, and in another direction
in another part, with a short straight portion
between. This reversal of the spirals after
fixation sometimes occurs only once, some-
times as much as seven or eight times, but
the number of times it appears in one
direction is always equal to the number
of times in which it appears in another.
68 OF PLANTS [chap.
The reason for this is to be found in the
mechanical necessity for preventing excessive
torsion. We have seen that a twining plant,
as it binds its spiral curve round a support,
develops a spiral twist also. This twisting
involves a twisting of the axis in the same
direction, which, if persisted in for too long in
the same direction, would ultimately burst the
tendril. But if just as many turns are subse-
quently taken by the spiral in the opposite
direction, the strain involved by the twisting
of the axis is removed.
I can the more cheerfully leave this part of
my subject somewhat incomplete, because the
vast majority of twining and tendril plants still
await investigation by more competent ob-
servers; nor does it seem possible to explain
their ways until we understand a little better
how the forces of gravity and light act upon
processes of growth. In many instances the
resulting spiral may have originated in what
we should call " mere accident, " or, as Darwin
expressed it, in "causes which are not ap-
parent to us." But several of the problems
presented seem to go much deeper, and even
to touch those elemental laws which govern
universal life and strength and movement, and
give their final proportions to the handiwork
of man.
The investigations into the system on
in.] BONNETS THEORY 69
which leaves are arranged upon a stem,
begun by Leonardo four centuries ago,
have only just arrived at something ap-
proaching to an intelligibly philosophical ex-
planation. For a hundred and fifty years, what
is known as the " Spiral Theory " of Bonnet,
formed the foundation of all studies in
phyllotaxis ; that is to say, in the consideration
of a stem bearing leaves as an axis and its
appendages. In 1754 Botanists were still
dominated by the doctrines of Constancy
of Species, and as morphology dealt solely
with adult structures, it arrived at the very
simple ideal of a formal account of the
framework of the fully matured stem, leaves,
flowers, and fruit; developmental stages, and
buds, being considered as unessential. Bonnet
therefore took a mature stem, and chose upon
it a leaf (A), which came exactly above another
(B). He then showed that the intermediate
leaves were arranged as a spiral, exactly as if
(B) were the bottom point on the cylinder
in fig. 3, and the intermediate leaves were
arranged along the string until they reached
(A) at the topmost point of the cylinder. In
this way he determined what is known as the
64 two-fifth spiral," in which the sixth leaf is
inserted exactly over the first of a spiral series,
which makes two complete revolutions of the
stem. By the help of the mathematician
70 OF PLANTS [chap.
Calandrini, he formulated a correct geometrical
conception of a helix, with parallel screw-thread
winding round the cylindrical stem. This
mathematical conception was arranged to
fit certain definite facts, and with this as a
basis, Schimper and Braun (1830-35) raised
"an enormous edifice of beautifully precise
nomenclature."
But by degrees appeared the results of
such ideas as were contained in Goethe's
Theory of the Metamorphosis of Leaves,
in Lamarck's Researches into Development
and Heredity, in Von Mohl's Discovery
of the Growing Substance in Plants, in
Darwin's great Hypothesis of Evolution.
By degrees the type plant of the new
morphologist became the growing body, as
seen in the growth of the members, growth of
the axes, growth of the whole individual,
growth of the race. But while critics ex-
claimed that Bonnet's mathematical conception
had been gratuitously introduced into the plant,
and was "mere playing with the properties
of numbers," they did not apparently realise
what Bonnet himself thoroughly understood,
that, being ignorant of protoplasmic growth,
he dealt solely with adult structures which
had ceased growing.
At last Mr A. H. Church, a well-known
and distinguished botanist in Oxford, came
in.] CHURCH'S THEORY 71
forward with a new mathematical conception,
founded on the new mathematical data
afforded by the transition of the morphological
standpoint from that of adult construction to
that of growing systems* As a starting-point
for such a conception, Mr Church very
properly propounded a certain ideal condition.
Just as, in the consideration of the Newtonian
laws of motion, the purely abstract and
mathematical conception of " uniform motion "
precedes that of varying motion, so the
growth of a mass of protoplasm may be
conceived as a " uniform growth," expansion
taking place around a hypothetical central
point. From this, Mr Church deduces the
hypothesis that logarithmic spiral curves (see
fig. 35), with the straight line and circle as
limiting cases, are the sole curves of uniform
growth expansion. Spiral phyllotaxis must,
in future, therefore be based on a logarithmic
spiral on a plane surface, and not on Bonnet's
old idea of a helix winding on a cylinder, which
is merely the expression of the attainment of
uniform volume by members in a spiral series,
and which, if carried on to a plane as a spiral
with equal screw-thread, would become a
spiral of Archimedes.
Of course, when applied to the living, and
admittedly irregular, growing plant, the con-
ception of a logarithmic spiral would be as
72 OF PLANTS [chap. in.
difficult to prove by actual measurement as
was Bonnet's theoretical helix. But now the
standpoint is changed, it becomes possible not
only to deal with uniformly growing systems,
to deduce mathematically their various pro-
perties, to watch them (as it were) grow on
paper, but also (as soon as the properties of
uniform growth are ascertained) to study the
possibility of varying rates of growth, and to
state the growth of an irregular body in
mathematical terms as precise as those which
indicate the erratic orbit of a comet.
We shall find that the logarithmic spiral
occurs again in connection with organic
growth in later pages of this book, and I shall
have occasion,1 before the end, to consider
some further results which follow from Mr
Church's valuable and intricate researches.
For the present I must conclude, with this
brief notice of them, that portion of my
subject which has to do more particularly with
Botany.
1 See pages 124 and 185.
CHAPTER IV
OF SHELLS
" Year after year beheld the silent toil
That spread his lustrous coil ;
Still as the spiral grew.
He left the past year's dwelling for the new,
Stole with soft step its shining archway through,
Built up its idle door,
Stretched in his last-found home and knew the
old no more.' '
TTERY early in the chain of
animal creation the spiral ar-
£ rangement makes its appear-
J3 ance.1 The cilia on the top of
la
^ 1 Though I have purposely refrained,
% for the present, from introducing pictures
10 S of microscopical specimens into this
*"". 2 Essay, I must refer the biological student
£ g who desires them to the magnificent
js illustrations in Dr Friedrich Hitter v.
J? Stein's "Der Organismus der Infusions-
| thiere" (fol. Leipzig, 1867). In the
a second Division, he will find left-handed
§ spiral lines on the body of Spirostomum
ambiguum (Taf. III.) ; a beautiful spiral
curve in the filaments surrounding the
head of Stentor Polymorphous (VI.) ; and
spirals of a distinctly logarithmic character in Stentor
coeruleus (VI.), S. Roeselii and 8. igneus (VIII. ), and
73
74 OF SHELLS [chap.
Vorticella are set in a spiral, possibly with
the object of creating a vortex in the
water that would suck food towards the
mouth. In the tube-building worm called
Sabella, the gills are set in a very beautiful
spiral, no doubt with much the same effect
of converging currents. This organism is
mentioned by Herbert Spencer, but the best
picture of it I have seen is in the Atlas
to " Le Regne Animal," by G. Cuvier, edited
by a number of his disciples (Paris : Fortin,
Masson et Cie), which gives a very beautiful
drawing of Sabella unispira on Plate IV. in
the section " Annelides." An instantaneous
photographic record of the spiral movement
of the cilia of Vorticella was published by
E. J. Marey in "Le Mouvement" (Paris,
1894), since translated by Eric Pritchard.
The case made by the larvae of the Caddis-
fly (Phryganeida) is beautifully formed by a
ribbon twisted up into a right-handed spiral.
In the enlarged drawing of this in fig. 15
the creature's antennse are seen protruding
from the top of its case. In some sharks
the egg-capsules show a spiral, of which I
S. multiformis (IX.). In the third Division of the same
work, "Der Organismus der Flagellaten " (Taf. XX.), a
good example of right-handed spiral lines on the body is
shown in Euglena oxyuris (figs. 4 and 5), while an especially-
well-marked specimen of the left-handed spiral is to be seen
in Euglena sjpirogyra (fig. 7).
iv.]
VITAL FORCES
75
reproduce an example (of a dextral helix) in
Cestracion philippi (fig. 16) ; and the queer
spiral arrangement of certain sharks' teeth has
been already noticed on p. 42.
The spiral of the cochlea hidden in the ear
is an unmistakable proof that the bone
containing it belongs to a mammal, and it is
thus that ambitious lizards are unmasked.
Hermann von Meyer once accidentally dropped
a skull which he thought be-
longed to a lizard, and the break-
age revealed the cochlea, proving
that the bones belonged to a
mammal which was christened
Zeuglodon. The same arrange-
ment has an even more intimate
connection with the most im-
portant organ in the human
body, for Pettigrew showed that
the process of the fibres in the
ventricles runs in spiral lines
from the tip of the base of the heart, so
that the muscular constriction of the systole
is of the nature of a twist or screw. There
are, in fact, certain vital forces in Nature
which are invariably expressed in a spiral.
It has, for instance, been shown that the
relation of the direction of the magnetic force
due to an electric current to the direction of
that current itself is the relation involved in
[<<l^s
Fig. 16.
Capsule of
Shark's Egg.
76 OF SHELLS [chap.
a right-handed screw. Astronomers, too, are
now aware that the spiral nebulae, though
generally discredited when originally an-
nounced by Lord Rosse, were photographed
between 1880 and 1890, and usually exhibit
left-handed whorls.
Some of the most beautiful and interesting
spiral formations in Nature are, as Leonardo
knew, to be found in horns, a pretty pair of
which (from a Bush-buck, shot in 1878) is
shown in fig. 17. It will hardly be be-
lieved that in the year these were brought
home, and for twenty years longer, there
existed no proper scientific terminology for
the direction of the spirals in horns, found
in both fossil and living animals. In a
pamphlet on " Spiral Growth," published by
Dr George Wherry in 1898, it was first
pointed out that the horns of the Koodoo
exhibited a right-handed spiral on the left
side of his head, and a left-handed spiral on
the right side of his head. In February 1901
another leaflet by the same writer noticed
that "the spiral horns of animals, such as
the Koodoo, are symmetrically arranged, are
right and left by certain rules to which
few exceptions only are found." A good
deal of somewhat nebulous newspaper con-
troversy arose on the subject ; but as many
statements were made without sufficient proof,
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iv.] TWISTS AND CURVES 77
and many words were used without any-
proper definition of their meaning, it may-
be as well for me to give a few facts and
illustrations here of what is only one branch
of my subject, but is none the less deserving
of far more extended study than I can give it
in this place.
Even from the little already said as to spiral
formations in Nature or Art, it must be obvious
that the word " spiral " cannot be used in any
argument unless it is carefully qualified and
defined. It is obvious, for instance, that no
critical comparisons are possible between such
a conical helix as that exhibited in fig. 26,
and such a spiral curve as that shown in
fig. 34. We might, indeed, compare the twisted
horns of a Markhor (fig. 196) to such a
conical helix as that in fig. 27 ; but the horns
of the Highland Ram (fig. 20a) are evidently
a different kind of spiral, which can better be
compared to such a mathematical curve as
that which has been drawn in fig. 35. In
other words, we must carefully distinguish
between the spiral twist, about an axis which
coincides with that of the horn; and the
spiral curve, about an axis which would
be perpendicular to that of the horn, if the
horn were a flat spiral. In fig. 18 these
two different forms of spiral can be seen in
the same pair of horns. From C to D
.
78 OF SHELLS [chap.
runs the spiral twist about the axis CD.
But in the growth of the horn from C,
there is a point A, up to which a curve only
is apparent, and if this curve were produced,
it would show the spiral CAB, about the
axis CB.
It will save our space considerably, if we
adopt the suggestion that horns exhibiting
right-handed spirals on the right side of the
head, and left-handed spirals on the left side
of the head, should be called " homonymous."
The obvious corollary is that horns which
exhibit right-handed spirals on the left side
of the head, and left-handed spirals on the
right side of the head, may be described as
" heteronomous." Owing to a lax use of
words, it has been thought that all wild
animals prefer the heteronomous arrangement,
while all tame animals show a homonymous
formation. You may, for instance, see a pair
of Elands (Taurotragus oryx)&t the present time
in the Zoological Gardens in Regent's Park.
One of them was bred in South Africa,
the other in France. Both of them show
clearly the heteronomous arrangement which
is observable in a Sing- sing Water-buck (Cobus
unctuosus) not far off them. So far, there-
fore, they support the suggestion described
above ; and as the animal bred in France
exhibits a spiral with a slightly longer pitch,
iv.] EFFECT OF DOMESTICITY 79
it is conceivable that this spiral may straighten
out before beginning to turn the other way.
This would mean that the effect of domesticity
upon spiral horns would be that the heterono-
mous arrangement of the wild varieties
became in time the homonymous arrange-
ment suggested as proper to tame animals.
Such a result is not only based on an incorrect
use of language ; it is also contradicted by the
facts.
In the head of Tragelaphus angasi, shown in
fig. 18, it would be correct to say that the
right-handed twist on the left horn (from C
to D) is an example of the heteronomous
arrangement of spirals in a wild animal.
But if we imagine the curve CA to be
continued to B, we find that it would form
a left-handed spiral, and that, being on the
left side, it would exhibit the homonymous
arrangement. If the same horn, therefore,
may exhibit a right-handed twist and a left-
handed curve, the argument concerning the
effects of domesticity in horned animals must
be limited either to the twist or to the curve
in dealing with the same kinds of animals, and
should hold good in both, if it is to be accepted
at all.
Taking the spiral twist first, we find it most
often in goats and antelopes, and the most
markedly heteronomous arrangement exists
80
OF SHELLS
[chap.
in the Markhor (fig. 196) of which I have
reproduced a drawing of the Pir Panjal race
( Capra falconeri cashmiriensis). Compare
the horns of this wild goat writh those of the
domesticated Angora (fig. 19a). Here we
FlQ. 19.
B
khor.
Spiral Twist.
A
Angora,
find an arrangement which is just as clearly
homonymous ; for the twist on the left horn
is a left-handed twist, and the curves are
homonymous as well. So far then as the
twist is concerned, we do find that all wild
iv.] HETERONOMOUS HORNS 81
animals enjoy the heteronomous arrangement,
and some tame animals show homonymous
spirals.
But when we examine horns in which
the prominent feature of the spiral is its
curve, as is the case with nearly all sheep, we
find that no wild varieties exhibit the heterono-
mous formation, for the homonymous arrange-
ment, which is convenient and necessary, is
common to both wild and tame, to
Alaskan Bighorn, Argali, and Pamir sheep
(fig. 20, c9 e, d) as well as to the High-
land and the Merino Ram (fig 20, a, b).
Evidently, when horns grow in curves,
the homonymous formation is the best,
inasmuch as a left horn which produced a
right-handed spiral curve would not only be
quite useless, either for offence or feeding, but
would become positively dangerous to the
animal when the ingrowing horn began to
penetrate its skull, or even its back, a
freak of nature which has been observed
to occur when normal growth has been
affected by injury of the base, as we noticed
in the case of the elephant's tusk in fig. 6.
In the few cases in which the curves exhibit
heteronomous formation, the horn is pre-
vented from doing harm by being given
a twist as well, which carries the dangerous
point off in another direction. It would be
F
-
82
OF SHELLS
[chap.
I
W
a
P*
iv.] SOME EXCEPTIONS 83
interesting if it could be established that this
latter peculiarity was exhibited by animals
which were midway between sheep and
goats, and therefore possessed a little of the
peculiarities of both. There is no doubt that
a horn with a spiral twist would be stronger
mechanically than either a plain cone, or a
spiral curve, as may be seen by the twisted
plaits on the columella of a shell, or the
twisted fibre in a twining plant. So a curved
horn may very possibly develop a twist as
well, if strengthening were necessary, and it
is obvious that the twisted horns of goats
and antelopes are stronger than the mere
curves usually exhibited in the horns of the
less pugnacious sheep.
There is an exception in each class which
has come under my observation. The
Abyssinian Ibex (Capra walie) has no spiral
twist whatever, but only a curve; and the
Wallachian sheep with its queer spiral horns
is even more peculiar, in that it shows no
curve whatever, and has a very strongly
marked and close spiral twist like a corkscrew,
of heteronomous formation. This animal is
found in Crete, Wallachia, Hungary, and
Western Asia, and as nothing of it but its
horns has yet reached this country, it is
actually impossible to say whether it is a
sheep or a goat, for the presence or absence
84 OF SHELLS [chap.
of certain glands cannot be established. But
judging from the model at South Kensington,
and from five photographs in the possession of
Mr Rowland Ward, I am inclined to believe
that these characteristic horns are due to a
cross of Markhor blood, more particularly of the
Sulieman Markhor (Capra falconeri Jerdoni),
which has very closely twisted spiral horns.
But one of Mr Ward's "Wallachian sheep"
seems to show the probability of this cross even
more, for its horns exhibit the true Markhor
curve at the beginning, which we noticed in
fig. 196, and continue in a far more open
spiral twist.
My last observations in this part of the
subject would be that all horns which show
heteronomous twists also exhibit the homony-
mous curves seen in fig. 18. But the Situtunga
(Tragelaphus spekei) shows the curves above
its forehead to be very clearly heteronomous,
and they are completed in heteronomous
spiral twists, which gives a shape very much
like that of the conventional lyre.
So far, therefore, as I have been able to go,
it seems that when the spiral twist occurs, its
better formation is the heteronomous forma-
tion, and that therefore this is the formation
most usually found, even when the twist
occurs in an animal which usually exhibits a
homonymous curve. In the case of curves, on
iv.] BYPATHS OF RESEARCH 85
the other hand, the homonymous formation is
practically inevitable, and the heteronomous
only occurs in combination with a twist. The
origin of these two distinct kinds of spirals in
horns does not appear to have been in-
vestigated. The beginning of the divergence
is no doubt to be found in some remote
ancestral type, long before Man exercised any
influence upon animals whatever, or even
appeared upon the earth at all. Since the
effects of domestication upon a particular breed
would take a very long time indeed to make
itself visible in this way, I am inclined to
think that these spiral formations are rather
the accompaniments of a differentiation in
species than the result of any domestication of
a breed, otherwise, how is it that differences
are observed in the spirals exhibited by closely
allied animals ? This study of horns, which
Leonardo began in one of the Manuscripts
preserved at Windsor, on which he has
sketched a head, very like that shown in fig.
20a, is a bypath in biological research 1 that will
offer results as interesting as an investigation
(for instance) into the growth of hair. We do
not at present know why the growth of hair in
1 Another bypath of biology that may lead us to the
most unexpected results is the investigation by Professor
Poulton and others into animal coloration. It appears
that animals are usually dark above and white beneath,
86 OF SHELLS [cha*.
some antelopes and in all African buffaloes is
perfectly normal from head to tail, whereas in
other antelopes you find the growth reversed
from shoulder to head, and in all Indian
buffaloes it is reversed from tail to head.
There is a reason, or there would not be the
difference. And there is a reason, too, for the
spiral formations in horns. In this place, I can
but state the facts I have observed, and leave
to others, who are better qualified, the task
of explanation. I cannot agree with Dr
Wherry's further suggestion that the funnel
created by the spiral curve of the great horn of
Ovis nivicola enables the small ear (placed "at
the apex of the hollow cone ") to distinguish
sounds better, just as a man often hears more
clearly when he places his hand behind and
round his ear. Like many other theories of a
similar nature, this stands in need of further
proof and investigation, though it is a good
example of the interest that may be found in
any consideration of the causes or origins of
spiral growth.
Certain brachiopods contain very beautiful
because this arrangement is exactly the opposite of what
happens when light falls upon a solid body which need not
be concealed. A normally coloured animal in its normal
surroundings will, therefore, not seem to be solid, and will
be practically indistinguishable at a short distance against
a background of colour and pattern similar to its own.
iv.] ORIGIN OV SHELLS 87
calcareous spiral arm-supports, formed by a
ribbon of lime, and attached to the dorsal
valve. In Zygospira modesta (Hudson River
Group), these spiral cones are directed inwards ;
in Spirifer mucronatus (Devonian) they are
directed outward and backward, and formed of
many whorls ; in Koninckina leonhardi (Trias)
the double arm-supports are flat spirals, instead
of cones set on their edge, and are each com-
posed of two lamellae.
In shells I have found the most exquisite
examples of spirality in all the natural
kingdom, and the formation of spirals by
the shell-fish seems to be still in need of a
complete scientific explanation.
When an elastic "bendable" substance is
growing above an object, and dropping at its
end, it might sometimes take the form of
a plane spiral. But if, during its growth, it lops
over at all to one side, it usually lops over to the
left, the result of which (as we observed in
shavings) is the usual right-handed spiral, and
shells exhibiting this are called by con-
chologists " leiotropic," because a man walking
up a right-handed spiral staircase would be
always turning to the left (see fig. 28, and
compare fig. 7). Very rarely they lop over
to the right, and the result is the rare left-
handed spiral of the " dexiotropic " shell (see
fig. 8).
88 OF SHELLS [chap.
As an organism of this kind grows, if the
new piece were of accurately rectangular
formation, thus : □, the result would be
growth in a continued straight line. But it
never is ; for the dorsal surface of a shell-fish is
thin and ductile, while the ventral surface is
harder, and contains muscles which continually
exercise a certain pull upon the tissue ; so that
the new growth is usually of this form : (Z7
As, therefore, the dorsal surface expands more
easily than the ventral, while the creature goes
on developing, the result is a continuation and
emphasis of the spiral form, thus :
It is only necessary to remember that this
spiral is growing vertically while it also grows
in length, and you may add the pull of gravity
to the other forces at work while the creature
increases in bulk and weight, until the spiral
formation of the shell-fish becomes a little more
intelligible. You may produce the same
formation by squeezing paint out of a tube, or
by the toy called " Pharaoh's serpents," which
is a more exact parallel, because the " growth "
comes from beneath, and may be made to
exhibit either a sinistral or a dextral formation
(see p. 41).
In considering the reasons why a shell
iv.] SINISTRAL SHELLS 89
should be sinistral rather than dextral, I must
distinguish between those sinistral shells
which are "sports/' or rare exceptions to the
dextral rule common in their species, and
those shells which are sinistral as a rule of
their species. There is yet a third distinction,
which must be made later.
Turrilites catenulatus always exhibits a
conical sinistral spiral. Turrilites costatus, a
fossil gastropod, commonly called the " screw-
shell," is found in the Portland formation
as a rule. Other left - handed species are
Columna flammea, from Prince's Island in
the Gulf of Guinea; Miratesta, a fresh-
water shell from Celebes ; Amphidromus
perversus from Java ; the pond-snails Physa
fontinalis in Europe, and P. heterostropha of
America.
The sinistral form of Voluta vespertilio
(figs. 54 and 57) is, however, the exception
to the rule of the species, which is found on
the Italian coasts of the Mediterranean, and
an Italian collector would be more likely to
have the sinistral form of a common shell
than its ordinary growth. At the present
day, Mr Fulton informs me that specimens
of the sinistral Buccinum undatum, though
not common, can be bought for a few
shillings. A Billingsgate porter thinks he
has a rare prize when he finds it, and
90 OP SHELLS [cha*.
is greatly disappointed when he discovers
it is not worth gold. Chrysodomus antiquus,
a fossil sinistral whelk, of which Mr Morton
Loder, of Woodbridge, has sent me an ex-
cellent specimen, is too common to be bought
by dealers at all. The genus Amphidromus
is about equally divided into dextral and
sinistral species. But in cases where a shell
only exhibits the sinistral specimens in its
fossil form, and is dextral in all living
examples, I have been unable to determine,
as yet, any reason for the survival.
The third distinction to be made in this
matter is in such cases as Spirialis, Limacina,
Meladromus, and Lanistes (see p. 51), in
which the shell is sinistral but the animal is
dextral. Here Simroth, Von Thering, and
Pelseneer explain that the shell is really
ultra-dextral ; that is to say, the whorls have
been, as it were, flattened, as in Planorbis,
then the spire has been still further pushed
downwards, until the whole is turned inside out,
becoming sinistral with its original dextral
animal. The proof that this queer process
has in some way occurred, is arguable from
the fact that every dextral shell has a sinistral
twist to the operculum, with nucleus near
the columella, and vice versd (see fig. 38) ;
but in " ultra-dextral " shells, the operculum
is sinistral, in spite of occurring in what looks
iv.] THE NAUTILUS 91
like a sinistral shell. There are also instances
of " ultra-sinistral " shells, which appear to be
dextral though their orifices are sinistral, as
in the fresh-water Pompholyx from North
America, and Choanomphalus from Lake
Baikal. Turbonilla is sinistral in its
embryonic form, but becomes dextral as
an adult.
If we take the Telescopium shown in fig.
27 as an example of a conical spiral, the
Nautilus pompilius in fig. 34 will be a good
instance of the flat spiral, in which all the
whorls are practically in one plane. In this
picture, the little projection noticeable in each
compartment of the shell is the siphuncle,
a membranous tube perforating the septa,
which Owen thought was connected with the
pericardium, and which may serve to lighten
the shell by the passage of some gas into its
various chambers. In the Nautilus it nearly
always projects backwards, but in the
Ammonites it nearly always projects forwards.
Among the Stephanoceratidae, Crioceras hi-
furcatum has disconnected whorls, as if the
various coils of an Ammonite had not
joined together, and it looks something like
a ram's horn, or a rather complicated
hook. Oncyloceras spinigerum is a fossil
tetrabranchiate cephalopod, in which the
whorls are also disconnected. Siliquaria
92 OF SHELLS [chap.
anguina has a shell that begins in a close
spiral and ends in irregular separated coils.
Cylindrella, the cylinder- snail of the West
India islands, a palmonate gastropod of spiral
form, has the last whorl detached from the
rest, with a circular mouth-opening.
In the British Museum of South Kensington,
there are very fine examples of Macroscaphites
gigas, and Macroscaphites ivanii, which look
like Ammonites beginning to unroll themselves ;
and if the logarithmic curve in fig. 35 be
taken as the expression of " uniform growth "
in all organic matter, as Mr Church suggests
it may be used in plant-protoplasm, it may be
conceived as possible that as the surviving
Nautilus (fig. 34) differs from it in taking a
wider sweep, while the fossil Ammonite differs
in exhibiting a tighter spiral, so the form of
Macroscaphites may represent the tendency of
a creature more recent than the Ammonite to
expand its coil, and get a larger space for the
life and growth of the animal it shelters.
The position of the siphuncle may also have
some connection with the causes of survival,
for while it is on the convex side of Goniatites,
and on the concave side of Clymenia, it is
placed in the middle in the Nautilus. In
" Les Enchainements du Monde Animal dans
les Temps Geologiques" (Paris 1883), M.
Albert Gaudry shows that Orthoceras (with its
iv.] THE SIPHUNCLE 93
siphuncle in the middle) is in fact, as Barrande
thought, " a straight Nautilus/5 and the inter-
mediate steps in development may be traced
through Aploceras, which shows a slight curva-
ture to the right at the thin end, and Nautil-
oceras, a hook-like formation with disconnected
whorls. In the same way M. Gaudry suggests
that Melia (with its siphuncle on the right side)
becomes Cyrtoceras when the tip shows a
slight curvature, and so may be supposed to
pass through such forms as Gyroceras and
Ophidioceras to the Ammonite.
CHAPTER V
COMPARISONS
" Small and pure as a pearl. . .
Frail but a work divine
Made so fairily well
With delicate spire and whorl. . .
A miracle of design."
TN such a shell as Solarium maximum
■*■ (fig. 2, a, b)9 the simpler form of spiral
arrangement is prettily exemplified, and it
is so easy to imagine walking in at the mouth
(or entrance), and continually turning to the
left until the top is reached, that this shell
has been commonly called the "staircase
shell."
A connection between shells and spiral
staircases, in the minds of those who were
responsible for scientific terminology as it is
now accepted, has been already indicated in
the words " leiotropic "^ and ' ' dexiotropic,"
which are otherwise inexplicably the reverse
of the spirals they describe. But it is still
94
II
Fig. 21.
Spiral Staircase, Palazzo Contarini, Venice.
[To face page 95,
CHAP. V.]
SCALA DEL BOVOLO
95
further suggested by the nomenclature of
some well-known architectural treasures in
Italy. At Fiesole, for example, in the
convent of San Domenico, there is a flight
of eight steps (leading down to the cloister)
which is so exquisitely arranged in the form of
a shell that the little building is called the
"Scala della Conchiglia." At
Venice a more famous example
may be found [in the Palazzo
Contarini, near the " Congre-
gazione di Carita" (No. 4299),
which is reached through the (J
Calle della Vida out of the
Campo Manin. Its shape has
earned it the name of the
Scala del Bovolo (fig. 21), and
I am tempted to think that the
architect of this dextral helix,
with its exquisite rising spiral of light
archways, may have seen the shell so aptly
called Scalaria scalaris (fig. 22), which
exhibits exactly the same formation. In
this shell the mouth or entrance has
gradually grown round and round with the
growth of the inhabitant, leaving a little
colonnette behind it as it moved, until it
reached the place which is equivalent to the
door in the staircase to which I compare the
shell. How infinitely more beautiful the
Fig. 22.
Scalaria scalaris.
96 COMPARISONS [chap.
spiral formation of ascending curves in the
Scala del Bovolo is than a mere system of
super-imposed circles (even when arches and
colonnettes are similarly added) may be seen
from a comparison of the whole height of
this staircase (fig. 23) with the Campanile at
Pisa (fig. 24). But the spiral formation itself
is not invariably a happy thought in every
architectural position. Some such idea of
growth, of support, of strength, as is shown
in the " Prentice's Pillar," seems as essential
to it in Art as in Nature. The staircase of
the Rundthor at Copenhagen, is, for instance,
a far more satisfactory example than the
twisted copper spire in the same locality; or
than the corkscrew- shaped spire of Gelnhausen,
near Frankfort on the Main; or than the
stone spirals in one of the small steeples of
the Palais de Justice at Rouen, near the Rue
Jeanne d'Arc.1 Mere imitation of externals
without structural necessity, is, in fact, as
barren here as it must ever be. Perhaps
this is why I can never admire the twisted
1 I am informed that the twisted spire at Chesterfield,
which is made of a timber frame covered with metal, was
not originally constructed in this screw-like form, but has
been twisted into its present shape by the decay and
partial failure of some timbers, an accidental origin for an
architectural form which must carefully be distinguished
from a structural shape intentionally created from the
first,
Fig. 23.
Scala del Bovolo, Palazzo Contarirr,
Venice.
Fig. 24.
The Tower of Pisa.
[To face page 96.
Fig. 25.
Escalier de la Reine Berthe, Chartres.
[To face page 97.
v.]
CHARTRES STAIRCASE
97
chimneys so often seen in Tudor buildings, or
even such fine sinistral spirals of brickwork as
are to be seen in the chimneys at Framling-
ham Castle. Even when in its right place,
in a staircase, the spiral needs clever hand-
ling if it is to be effective,
as may be seen in the
clumsiness of the brickwork
in the house of Tristan
l'Hermite at Tours, and the
ambitious failure of the
clustered sinistral spiral in
the stone stairway of the
cloisters in the same town.
In each case the steps, too,
are straight and inartistic.
An even more delightful
example of the close con-
nection between a good
architect's plans and the
exquisite lines of Nature is
to be found in the stairway
called " Escalier de la Reine
Berthe" at Chartres (fig.
25). It exhibits the delicate
exterior ascending dextral helix, and even
the top of Mitra papalis (fig. 26) with
extraordinary faithfulness, and the parallel
becomes even more complete when the
position of the darkened doorway is com-
G
Fig. 26.
Mitra papalis.
98
COMPARISONS
[chap.
pared to that of the shadowy orifice of the
shell.
In Mitra papalis at this orifice, you will
observe the beginnings of three internal
spiral lines which suggest that the internal
arrangements of a shell have as much to teach
us as its exterior forms ; and a very beautiful
spiral may be seen by the aid of
the X-rays continuing through-
out the whole length of the
long-pointed shells so common
in the south. The clue is worth
following up, and a section
cut through such a shell as
Telescopium telescopium (fig. 27)
actually reveals an exquisitely
firm and elegant single spiral (a
dextral helix) rising round the
columella, that pillar which
supports the whole ; and this at
once reminds me of the spiral
in a staircase built in the old part of the
Chateau of Blois many years before Leonardo
was in France (fig. 28). But I do not for a
moment suggest that there was any conscious
comparison in the mind of the fifteenth-
century architect, and this for the very good
reason that the curve of his stairway and the
beautiful spiral rail (on which the left hand
would rest as one ascended) are both
Fig. 27.
TeUscopium
telescopium.
Fig. 28.
Staircase in the Old Wing of the Castle of Blois. [To face page J
v.] NATURE AND ART 99
susceptible of a simple architectural explana-
tion; so that all I should be inclined to say
of this comparison at present is that, as the
lines of the architecture are right, and fulfil
their purpose exactly, with an economy of
space and strength, and a sufficiency of
support, they were therefore very likely to be
in harmony with those lines which Nature,
the best of all artificers, has developed in her
shell. I should need more resemblances than
this to be satisfied that one might have been
taken from the other ; but, on the other hand,
I shall by no means reject such a possibility,
at the outset, as absurd ; for architecture is
full of such copies from Nature, as every
organically beautiful, constructive art must be,
and it is full of equally suggestive relics of
the simpler forms of shelter from which the
palace slowly grew. If the Egyptian pillar
is a copy of the lotus-plant, so the peculiar
shape of the Moorish and Saracen arch is a
survival of that wind-blown tent, with conical
top and bagging sides pegged closely in, which
was the habitation of the Bedouin.
CHAPTER VI
A VANISHED ART
" Qual pare a riguardar la Carisenda
Sotto 1 chinato, quand un nuvol vada
Sovr' essa si ched ella incontro penda :
Tal parve Anteo a me. ..."
— Dante.
]^TO one who looks with a seeing eye at the
finest of the buildings which Leonardo
da Vinci might have known, can fail to detect
an intense perception of that difference in detail
and harmony in relation to quantities of which
Nature is the great exemplar. The " straight
lines" of the Parthenon are in reality subtle
curves, and recent investigation has detected
a similar delicacy of constructive measurement
in the great Gothic cathedrals. The influence
of the study of flowers and leaves is especially
marked when the positions and proportions of
the best Byzantine arches ar£ examined in the
light of the laws which govern growth. How
slight and exquisite were the details on which
such laws depended no one could realise better
100
chap, vi.] LOST PRINCIPLES 101
than the painter who had studied the render-
ing of expression on a human countenance by
lines so delicate that the reason for the effect
produced was only visible to the few who
knew. The eye is even more influenced by
things which are usually "unseen" than by
things which are " obvious " ; and it is of the
essence of Beauty that her origin and cause
are hidden from those unworthy to appreciate
her.
Some of these origins and causes it may be
well to state here, for though they have been
emphasised by such acute artistic intellects
as Professor William Goodyear and Mr Julian
Moore, and though the first announcement
of their existence was made many years ago,
yet they have never been properly appreciated
by a public which must, after all, be the
ultimate arbiter of architectural taste, and
they are closely connected with those methods
of Leonardo with which we are now chiefly
interested.
The history of architectural theory has seen
a renaissance of the ideals called classical, and
a revival of the school known as " Gothic," of
which the former was incomparably the more
valuable, because the conditions of society
which made "the pointed style" possible in
England, and gave birth to the " Gothic "
school in the He de France, could never re-
102 A VANISHED ART [chap.
appear, and were an essential concomitant of
the architecture which expressed them. Yet
an omission of equal value was made by the
revivalists of both schools. The real " Gothic "
preserved certain delicate principles of con-
structive asymmetry, in the curves and
irregularities in the masonry of the old Greek
builders, but the "Renaissance" which
pretended to go back to ancient Greek and
Roman ideals, did not appreciate, even if it saw,
these slight divergencies from the rule of
thumb which were invisible to any but the
trained observer. In the same way, the
Gothic Revival, which attempted im-
possibilities by overlooking entirely the radical
changes which had occurred in contemporary
life, was fated still more fully to destruction by
its complete ignorance of the finer subtleties
of mediaeval art. We have no actual proof of
this lack of appreciation in each case, except
the proof provided by the buildings which
were themselves the products of these separate
revivals. For, apart from Vitruvius and from
the invaluable Note-book of the architect
Wilars de Honecort (1250), we have no real
contemporary record of the growth of
architectural principles until these theories
concerning slight divergence had been wholly
lost. Even the sentence in Vitruvius, which
seems directly to refer to them, was never
vi.] BAD WORKMANSHIP 103
understood until the nineteenth century, and
then only by the merest chance on the part of an
observer whose real work was never recognised.
These constructive refinements, however, died
out, not merely because no record existed
of them, but for the far more vital reason that
the public eye was no longer delicate enough
to appreciate them, though, as a matter of fact,
they are the real cause of beauty in the finest
of our old surviving buildings, which owe their
charm not merely to the kindly hand of time
but to the deep-laid skill of their builders.
When constructions have arisen which were
designed without that skill, even when they
are supposed to be exact copies of the old
originals, no lapse of time can ever lend them
a beauty which is no concern of theirs, as
may easily be seen in many smoke-begrimed
atrocities of modern London.
In these days, division of labour has lowered
the capacity of the individual artisan; and
machine-made work, accustoming the eye to
inartistic uniformity of ornamental detail, has
also destroyed its grasp of delicate structural
effects. In the old cathedrals, the mason and
the architect, the artist and the artisan, were
one. By the fifteenth century a Florentine,
Leon Battista Alberti, had separated the
architect from the builder. In England, it
was Inigo Jones who first invariably insisted
104 A VANISHED ART [chap.
that his wood and stone workers should copy
his designs instead of following their own
fancies. Each was a great man, yet each was
the unconscious origin of a great evil which
has befallen the art they loved.
The history of the discovery of curves in
ancient Greek, even in Egyptian, architecture,
is romantic and interesting enough. Every one
had read the passage which suggests them in
Vitruvius since 1500. Stuart and Revett had
measured the Parthenon in 1756. Lord
Elgin's workmen noticed nothing. In 1810
Cokerell had established the fact of entasis,
and in 1829 Donaldson saw the lean of the
columns. But in 1812 the translation of Vit-
ruvius, by Wilkins, only contained a note that
" this great refinement .... does not appear
to have entered into the execution of the work
of the ancients." Apparently it never occurred
to the translator that it was worth while measur-
ing " the work of the ancients/' before making
general statements about it. At last, in 1833,
Mr John Pennethorne discovered the un-
doubted existence of convex constructive
curves in the architraves of the second court of
the Theban Temple of Medinet Habou. Four
years afterwards he stood before the Parthenon,
with the passage from Vitruvius in his mind,
and saw those delicate irregularities which had
remained invisible throughout the passage of
vl] THE PARTHENON 105
so many unintelligent years. About the same
time two German architects, Hofer and
Schaubert, saw them too, and published their
discovery in the " Wiener Bauzeitung " of 1838.
Save in a private pamphlet, Pennethorne gave
nothing to the world till 1878, although in
1851 Francis Cranmer Penrose, helped by the
Dilettante Society, published the results of his
measurements of the Parthenon in " Principles
of Athenian Architecture."
Penrose showed that in this building no
two neighbouring capitals correspond in size,
diameters of columns are unequal, inter-
columnar spaces are irregular, the metope
spaces are of varying width, none of the
apparently vertical lines are true perpendiculars,
the columns all lean towards the centre of the
building, as do the side walls, the antae at the
angles lean forward, the architrave and frieze
lean backward, the main horizontal lines of
construction are in curves which rise in vertical
planes to the centre of each side, and these
curves do not form parallels. Professor
Goodyear, who completed the investigations of
Pennethorne at Medinet Habou, found that
similar curves existed in the Maison Carree,
and it is clear that while irregularities which
would be easily detected or obtrusively con-
spicuous were avoided, there was also an
unquestionable intention of avoiding exact
106 A VANISHED ART [chap.
ratios or mathematical correspondences wher-
ever such an avoidance was calculated to
produce a certain effect. That these devia-
tions were not the result of error in the work-
men, or of accidents in the lapse of centuries,
is also clear from Penrose's calculation that
the maximum deviation of the Parthenon in
the case of lines intended to correspond (as at
the two ends) is as little as the fiftieth part of
an inch, while the refinement of jointing in the
masonry is so great that the stones composing
the great steps have actually grown together
beneath the pressure of the columns they
support. It is in fact impossible to explain
such asymmetries as these, on the theory of
faulty work, of the use of varying materials
from different sources, or of subsequent
accidents, and the principles thus found to
be practised by the builders of the Parthenon,
have also been discovered by Professor
Goodyear to exist not merely in Egyptian,
Greek, and Roman buildings, but in Italo-
Byzantine, Byzantine-Romanesque, and Gothic
buildings, especially where Byzantine influence
has been strong, in obedience to laws which
fell into abeyance almost completely when the
classical Renaissance fully established itself.
Oblique plans are common in old churches,
and can easily be seen in such examples as St
Ouen at Rouen, or the choir arch in the parish
vi.] OLD ST PAUL'S 107
church of Wantage, where the deflection of
the building has been said to represent the
position of Christ's head upon the cross.
These instances, however, are of a grosser
nature than the curves in constructional line,
which I wish chiefly to emphasise, and which
may be seen in the walls of the nave of
Westminster Abbey. These are bent inwards
at about the height of the keystones of the
arches, and outwards above and below this
point, as Mr Julian Moore has shown. They
are not only structurally sound to this day,
but have retained a greater beauty than exists
in any of the numerous ruler-made copies in
different modern churches of the country. In
Evelyn's " Diary " there is a most interesting in-
dication of similar divergencies in Old St Paul's.
"Finding," he writes on 27th July 1665, "the
main building to recede outwards, it was the
opinion of Mr Chichly and Mr Prat that it
had been so built ah origine for an effect in
perspective, in regard of the height ; but I was,
with Dr Wren [Sir Christopher] quite of
another judgement, and so we entered it ; we
plumbed the uprights in several places."
This implies that two English architects of
the seventeenth century asserted a constructive
existence and an optical purpose for an out-
ward divergence from the perpendicular in the
vertical lines of the nave of a Gothic
108 A VANISHED ART [chap.
cathedral, and favoured the preservation of
the Gothic building as far as possible. To
Evelyn and Wren, however, the champions of
the Renaissance, the old church was " only
Gothic." Keen as they were, they had lost
something which two lesser men remembered.
Similar divergencies in St Mark's at Venice
have been equally overlooked by almost every
visitor. The piers and upper walls of the nave
lean outward to an extent of 18 inches out
of the perpendicular on each side, a devia-
tion which, had it been accidental, or later
than the original construction, would have
disintegrated the arches supporting the dome,
ruined the frescoes, and destroyed the building.
Again, in the choir of Sant' Ambrogio at Milan,
the main piers on the right and left lean out
nearly 6 inches from the perpendicular on
each side ; and a similar lean may be observed
in S. Maria della Pieve at Arezzo, where the
queer bent column in the choir gallery is
a conspicuous instance of the capricious and
eccentric forms occasionally developed by the
hatred of mathematical exactness.
A much more daring and aggressive instance
of divergence from accurate measurements is to
be found in the Campanile of Pisa Cathe-
dral, which I reproduced in fig. 24. This
astonishing structure is 179 feet in height, and
is no less than 13 feet out of the perpen-
vl] SYMMETROPHOBIA 109
dicular, a peculiarity which has given it the
name of the Leaning Tower of Pisa. This
lean is more accentuated in the three lowest
storeys, and above the third storey there is a
deliberate effort to return towards the per-
pendicular by means of a delicate series of
changes in the pitch of the columns on the
lower side, and by a slight rise in height of
the galleries on the same side. The reasons
for this have been somewhat too hastily and
generally taken from Vasari's explanation in
the " Lives," who attributes it to inexperience
of the peculiar soil of Pisa on the part of the
architects Guglielmo and Bonanno. They
endeavoured, he asserts, to rectify the settle-
ment of the foundations (which occurred, on
this theory, just when the third storey had
been completed) by endeavouring to build
back again to the perpendicular in 1174.
I cannot accept Vasari's explanation now
that Professor Goodyear's researches into
what may be called " symmetrophobia " have
been published. Vasari wrote some four
hundred years after the Campanile had been
built, some time after the Italian Renaissance
had cast its scorn on what was " only Gothic,"
and in days when the marriage of a daughter
of the Duke of Tuscany was celebrated by
whitewashing the Gothic frescoes of the
Duomo at Florence. Even if we accept
110 A VANISHED ART [chap.
Vasari's theory as to the Campanile alone, it
will not explain why similar divergencies occur
in contemporary buildings. The Baptistery
of the Cathedral, begun in 1173, also leans
17 inches out of the perpendicular, and the
plinth-blocks of its foundations tilt down
evenly and gradually for exactly 9 inches in
the direction of this lean. The Campanile
of S. Nicolo (built by Nicolo Pisano) leans
forward in the same way, and also curves
back again towards the perpendicular. The
facades of the Cathedral of Pisa, and of its
choir, both show a similar forward lean in
their original construction, curving back again
to the perpendicular.
Its Campanile, in fact, is not the result of
accident. It was originally built as it may
now be seen, the most remarkable combination
of Greco-Byzantine subtlety with mediaeval
exaltation in the age which enjoyed such tours
de force as the bent column of Arezzo, or
the Torre del Pubblico of Ravenna, or the
Garisenda Tower at Bologna, which is 163
feet high and 10 feet out of the perpendicular.
Goethe, whose Essay on Strassburg Cathedral
(about 1773) was a veritable re-discovery of
mediaeval principles of beauty, explained this
leaning tower as intentionally so built as to
attract the spectator's attention from the
numerous ordinary straight shafts ; which
vl] DELIBERATE ERROR 111
may well be true, if we are to believe
Benjamin of Tudela's statement to the effect
that there were ten thousand towers in Pisa
alone.
I cannot here commend the Campanile of
Pisa for its eccentric leaning construction any
more than for its superimposed circles (fig. 24),
which lose much of their effect by the equality
of their vertical divisions, but I quote it as
the most intelligible instance I know of the
deliberate avoidance of accuracy in construc-
tion for deliberate reasons. It is exaggerated,
and therefore fails where the more delicate
effects of the Parthenon succeed; but its
very conspicuous qualities give a very clear
example of that intentional mystification by
which the old builders strove to get a look of
life, of that nature which never grows by rule,
of those principles of growth which have
brought Nautilus pompilius so near to the
logarithmic spiral (figs. 34, 35) without exactly
reproducing the mathematical curve (see p. 185).
Ruskin noticed some such divergencies
from accurate measurement in the old Gothic
buildings of Venice, but apparently without
appreciating the value of Penrose's work on
the Parthenon.1 Yet the principles which
1 He emphasizes, for instance, the fact that the two
Eastern windows in the fa£ade of the Ducal Palace, which
overlooks the Riva de' Schiavoni, are lower than the other
112 A VANISHED ART [chap.
guided the Greek builders seem to have lasted
just as long as building was done from the
freehand drawings of the artist-mastermason.
No painter, even of to-day, would draw in a
door in one of his pictures with a rule and
compasses; he knows that there is a quality
in the natural work of hand and eye which
no artificial aids can give him. The old
Egyptians and the Greeks knew that, and the
tradition of it lasted on in a few cases of stone
construction even when the designs were
ruler-made, and when the irregularities of
handiwork had become the conventions of a
few skilled masons. As we have seen, two
English architects in the seventeenth century
recognised the existence of deliberate con-
structional inequalities. As late as the
eighteenth century these principles prevailed,
as may be seen in the "humped" pediment
of the Mansion House in London. Even to-
day the thatcher builds his cottage roof not
in straight lines, but in curves, which absorb
less rain-water, and he achieves a beauty
which is denied to the higher mathematics.
four, and his comment is : — "In this arrangement there is
one of the most remarkable instances I know of the daring
sacrifice of symmetry to convenience, which was noticed
in chap. vii. [' Stones of Venice/ vol. ii.] as one of the
chief noblenesses of the Gothic schools." But, of course,
questions of "convenience" do not enter into the "sym-
metrophobia " discovered by Penrose and Goodyear.
vi.] MODERN STREETS 113
The old streets were full of beautiful curves
which cannot be explained only on the theory
that twisting thoroughfares were more easy
to defend, or by the suggestion that the houses
grew up at haphazard. Neither of these
reasons can explain the beauty of the High
at Oxford, or the angle at which Magdalen
Tower is set to its own quad, or the
superiority of Regent Street and Piccadilly
to Victoria Street or the Edgeware Road.
The " whiff of grapeshot," has Haussmannised
modern Paris into a city of straight lines,
and the next step is the chessboard of the
American city, in which every thoroughfare
leads to nowhere in particular. When the
divergencies in building and in the laying out
of streets were almost forgotten, the principle
that underlay them still survived in that more
intimate form of architecture which is
furniture and domestic decoration. In the
best periods of Chippendale, or Hepplewhite,
or Sheraton, you find each step in a staircase
gently bowed outwards, or given a waving
outline (as in fig. 59) ; you find, too, that the
walls of the best rooms are given slight curves
horizontally as well as vertically; you find
the subtle inequalities of feeling handiwork
in settee, and chair, and screen. But the
modern " decorator " seems so fond of Euclid,
that the joys of the rectangle and the
H
114 A VANISHED ART [chap. vi.
parallelogram have swamped the charms of
Nature. He forgets that even so common
an object of his daily life as the human face
has two sides which are quite different the
one from the other.
Fortunately for us, Leonardo, that mighty
master of the human face, lived when these
principles were not so utterly forgotten as
they are now. He was indeed a painter
of the Renaissance, and the Renaissance
influenced all his life and art. But he
was a man whose personality broke a way
through the limitations of every style. He
was a student of Nature who had observed
that her divergencies were even more im-
portant than her reproductions, and who did
not even shrink from saying that the creative
imagination of the understanding man was
infinite in comparison with her. We shall
see therefore that when he chooses his
inspiration from such a natural object as
one of the shells to which he devoted
special study, it is not to imitate it slavishly,
but it is to reproduce those essential elements
in it which are the causes of its beauty, and to
mould them into new forms at the bidding of
his own artistic genius.
CHAPTER VII
THE NAUTILUS
;< . . . Wrecked is the ship of Pearl
And every chambered cell,
Where its dim dreaming life was wont to dwell
As the frail tenant shaped his growing shell,
Before thee lies revealed
Its irised ceiling rent, its sunless crypt unsealed."
MUST now return to fig. 27,
and endeavour to examine the
reasons for that spiral line which
encircles the central column of
the shell, for the plaits upon the
columella, as the conchologist
would say; for this is a little
structural detail which Leonardo
evidently noticed, and which has
not been thought worthy of any
adequate illustration by later bio-
logists. If it had ever become
necessary" (I can find no other
word) to strengthen the central
supporting column or columella,
Fig. 29. without too much enlarging it
ceHtheumgiganteum. OT adding to its weight, no better
formation than this spiral could be conceived,
115
116 THE NAUTILUS [chap.
and an almost exact parallel to it occurs in the
air-tubes or tracheae of insects and of plants.
Though of totally different origin, these air-
tubes in each case have a spiral thickening
of the wall, which strengthens them and keeps
them open, just like a spiral coil of wire round
a rubber garden-hose : engineers and mecha-
nicians are of course aware of this artful
method of strengthening a cylinder by means
of a spiral ; the cannons made by winding wire
round a central core are an obvious example.
I have not found any good drawing of this
formation in the tracheae of insects, though
I have seen an example under a microscope
in the British Museum of Natural History.
The tube has a delicate outside coating, and
after the death of the insect the spiral (which
thickens this coat) can be pulled out and
examined. In just the same way the spiral
band can be unrolled from the air-tube of a
plant, and this is very beautifully illustrated
in the " Text-book of Botany," by Julius
Sachs (Second Edition, Oxford, Clarendon
Press, 1882), which gives on page 114 the
longitudinal section of a fibro-vascular bundle
of Ricinus, drawn in fig. 95, s, and s', of that
book.
These spiral filaments are also found in
double and triple, as well as single, threads.
The spiral vessels of the Chinese Pitcher-
vil] AIR-TUBES 117
plant (Nepenthes) exhibit a quadruple thread,
as in fig. 54, and they have the further
peculiarity of being sinistral, like the rare
dexiotropic Voluta. These air-tubes are
found in the leaf-stalks ; they are closed ;
and their air-contents only permeate their
enclosing membrane, which is so delicate that
if the thread on the inner surface is uncoiled,
no trace of the thin membrane will be seen
except at the conical end of the ruptured
vessel. The air-vessels of insects are branched
and ramified so as to form a set of continuous
tubes, and are framed to resist pressure from
without by the elasticity of the fibre spirally
coiled within them.
It is only in the true spiral vessel that we
find air in each case. When plants have long
continuous tubes, forming ducts for fluid,
the internal strengthening is formed by a
combination of broken spirals and rings,
exactly as in the windpipe of the Dugong
we find a spiral cartilage terminating at
intervals in rings.
In Dr Schleiden's " Principles of Scientific
Botany," translated by Dr Edwin Lankester
(London : Longmans, 1849), the nature and
origin of spiral fibres (discovered by Malpighi)
is very carefully explained, with diagrams, on
pp. 42-47, and to this I must refer my readers,
for I have but space here to suggest that the
118 THE NAUTILUS [chap.
same process observable in these tubes may
have gone on in the formation of the spiral
round the columella of a shell ; and if so, it
might no doubt be further shown that shells
with only a single spiral need such strengthen-
ing less than those which possess eight, as
may be perhaps observed by a comparison
of fig. 27 with fig. 33. Charles Darwin
noticed that the clasp of a twining plant
round its support was definitely strengthened
by the spiral twist of its own actual fibre (see
p. 65), and the plaits on the columella may
possibly be the result of a similar set of
circumstances. In any case, this additional
growth has never yet been satisfactorily
explained; it may certainly be useful, as in
some way assisting the animal to keep firm
hold of its shell by means of a muscle
specially adapted to hold on by it. But
there are many large and thick shells in
which the columella is perfectly smooth,
so that in their case — whatever may be
true in other instances — the mode of attach-
ment must be different. The spiral line
which I am now considering begins at the
topmost and smallest chamber of the shell,
and continues growing with the external
growth to the largest chamber at the bottom.
It is possible, therefore, that this spiral may
have some intimate relation to the body of
VII.]
THE COLUMELLA
119
the animal in whose dwelling-place it occurs,
But this I am inclined to doubt, for the
reason that in Turritella lentiginoses (fig. 52) it
does not occur at all (though possibly because
the " strengthening " process was not yet
advisable), while if we take Telescopium teles-
copium (fig. 27) with its one spiral as the
fig. 30.
Voluta solandri.
Fig. 31.
Voluta pacijica.
beginning of a series, we shall find Ceritheum
giganteum (fig. 29) and Voluta solandri (fig.
30) with two spirals, Turbinella pirum (fig.
7) with three, Voluta vespertilio (fig. 53) with
four,1 Voluta pacifica (fig. 31) with five,
1 Cymbium, the boat-shell from the African coast, has four
plaits upon its columella, but its external formation is en-
tirely different to that of Voluta vespertilio (see p. 167).
120
THE NAUTILUS
[chap.
Turbinella fusus (fig. 32) with six, and Voluta
musica (fig. 33) with as many as eight, while
the number is even greater in Cymbiola
tuberculata and Harpula fulminata. What-
ever may be the real explanation of
these internal spirals which are reproduced
in every chamber of the shell, I do not
Fig. 32.
Turbinella, fusus.
Fig. 33.
Voluta musica.
therefore think that they can be so intimately
connected with the anatomy of the living
organism as with the structure of the
shelter which it fashions for its home ; for
though it may be true that the number of
"notches" in the columella-muscle of these
vil] ORGANIC CURVES 121
shell-fish corresponds with the number of
spirals round the columella in each case,
the question why these spirals exist remains
unanswered.
" It is better to take the line and leave the
shell/' said Ruskin, forbidding his pupils to
admire or use as ornament these "moulds
or coats of organism," however beautiful their
lines. He had evidently never looked inside
them.
But long before liuskin's criticisms had
become an artistic shibboleth, the inside of
shells had fortunately attracted the attention
of scientific men who possessed a combination
of talents as rare as it is fruitful. I think
it was Professor Freeman who said once that
the true historian should not only know
everything about something, but also some-
thing about everything. That may be a
counsel of perfection ; but it is an ideal that
is worth remembering in days when too much
specialisation sometimes darkens knowledge.
The biologist is great, and the mathematician
is great; but greater still is the man who
can combine some of the knowledge that is
in each without losing the accuracy of either.
Such a man, to some extent, must have been
Sir John Leslie, who was the first to indicate
the organic aspect of the curve-line known
to mathematicians as the logarithmic or
122 THE NAUTILUS [chap.
equiangular spiral (fig. 35). "This spiral/'
he wrote, "exactly resembles the general
form and elegant septa of the Nautilus"
("Geometrical Analysis and Geometry of
Curve Lines/' Edinburgh, 1821, p. 438). But
Canon Moseley of Cambridge went further.
He made an exact geometrical examination
of certain Turbine shells {Phil. Trans., 1838,
p. 351) which exhibited a spiral curve wound
round a central axis. This curve was found
to be logarithmic, and from it could be
framed a series of formulas by which the
other conditions could be predicted as they
were found to exist. The spires of the shell
increased in breadth in an exact successive
series, each one of which was a multiple, in
a certain ratio, of another. Thus the shell
must possess this form and could possess no
other, for its spiral logarithmic curve re-
produced itself.
Canon Moseley also noticed that the
operculum was remarkable for its geometrical
symmetry in the shells he examined; and
a process which no naturalist had yet dis-
covered was thereupon ascertained by means
of a mathematical calculation of the revolution
which the operculum of the shell must make
round its axis. By cutting any part of the
shell in the direction of the plane of its axis,
he found that every section gave a form
ID
CO
g
u.
Zfl
a
r3
»4
«,
CO
^1
r
vil] THE OPERCULUM 123
exactly similar to the form of the operculum ;
and so he proved in this way that the form
of a turbinated shell is produced by the
revolution of the perimeter of the figure
formed by the operculum round the axis of
the shell. In the Nautilus this figure is an
ellipse which revolves round its minor axis
and increases in geometrical progression with-
out ever changing its form as it revolves.
The operculum being of a fixed form, as the
shell grew it increased in size proportionately,
and thus formed a very convenient measure
of the shell itself and all its parts, inasmuch
as the curve of the shell possessed the peculiar
properties of the logarithmic spiral. Nor was
the extension of this animal's dwelling formed
by merely pushing the operculum forward,
as I suggested in speaking of the growth
of Scalaria scalaris (fig. 22), but by the
more precise method of depositing additional
matter along the lower margin of the shell
which formed the tangent of the curve. In
fig. 34 I have photographed a Nautilus shell
cut in two (N. pompilius from New Britain) so
as to show the spiral within, and this should
be compared with fig. 35, which was drawn
for me by a Senior Wrangler as an academic
example of a logarithmic or equiangular spiral,
without any reference to this paper or to the
shell of which it seems so close a copy.
1U THE NAUTILUS [chap.
It will be noticed here that Mr Church's
application of the logarithmic spiral, as an
ideal formula for " uniform growth" to
phyllotaxis, will serve the conchologist equally
well in the present instance; for certainly
this Nautilus is so nearly a logarithmic spiral
that the difference between the two can
easily be expressed in a mathematical formula
which will give — for the first time — an
accurate definition and description of the
shell. Professor Goodsir, and Mr Church
after him, have considered that the loga-
rithmic spiral is a manifestation of the law
which is at work in the increase of organic
bodies : " Spira Mirabilis, as Bernouilli called
it (in " Acta Eruditorum," 1691), and gave
it the motto — " Eadem Mutata Resurgo" —
because it reproduces itself both in its in-
volute and its evolute. If they are right,
the Ammonite, of which I reproduce an
example from the Lower Lias of Lyme
Regis (fig. 36), has not survived as a living
organism, because the sweep of its curve is
not wide enough for truly vital expansion,
and does not, in fact, correspond so nearly
to their Curve of perfect Growth as the
living Nautilus of fig. 35. It may be equally
significant that though the more generous
outlines of Argonauta Argo (fig. 37) do not
correspond to the logarithmic spiral even so
00
CO
o
.,
^
CO
vii.] SPIRA MIRABILIS 125
nearly as the Ammonite, yet they err on the
side of increase instead of decrease, and may
therefore have had a greater chance of survival.
Similar comparisons with the logarithmic spiral
may be profitably made in the case of the
beautiful external spirals clearly marked upon
the shells of Haliotida gigantea from the
Corean Archipelago ; of H. cunninghamii from
Australasia ; and of H. midae from the Cape
of Good Hope. The first of these three ex-
hibits an especially wide sweep in its outline
after the first curves of the spiral have begun
to grow and to expand. It has been already
noticed (see note to p. 73) that curves closely
approaching the logarithmic spiral occur in
such minute specimens of life as the In-
fusoria, described by Stein, especially in Stentor
Coeruleus ; so that Sir John Leslie's recog-
nition of the " organic aspect " of this curve
was perhaps wiser than he realised.
Biologists may not see anything very pro-
found in the approximation here illustrated
of a logarithmic spiral to a shell; for they
know that the spiral curves in the Nautilus
are due to growth and gravity acting on an
elastic substance, and mathematicians tell them
that the logarithmic curve merely expresses
in a convenient form certain common and
usual relations. Still, there is no doubt
whatever that the mathematical curve pro-
126 THE NAUTILUS [chap.
vides an interesting definition of the shell, and
I have never yet seen the apparently inevit-
able corollary to this simple fact, which would
be to explain what the component factors
are which would produce a logarithmic curve
in the Nautilus, and how those factors would
have to differ in order to produce some other
curve. I would humbly suggest this as an
interesting thesis to future examiners. A
careful inspection of fig. 34 will also reveal the
astonishing fact (which is common, I believe,
to every Nautilus and Ammonite) that the last
compartment in which the creature lived,
instead of being the largest of all, is distinctly
smaller than the one behind it ; a very pretty
instance of Nature's unexpected asymmetry,
which may be perhaps explained by the results
of increasing age in the inhabitant of the shell.
This is the only point in which Dr Oliver
Wendell Holmes does not seem quite accurate
about his biology in the beautiful lines on the
Nautilus, from which I have made several
quotations.
In fig. 38 I reproduce a photograph of
the operculum of Turbo marmoratus. The
operculum of turbinidce has been called an
"eyestone," and a "sea-bean/' It is a horny
or shelly plate secreted by gastropods and
other molluscs, which serves to close the
aperture of the shell when the animal is
vil] SPEED OF ECLIPSE 127
retracted. In Trochus the spiral on the
inner side is as close as a watch-spring. In
Turbo olearius it shows a beautiful figure
like a logarithmic spiral with septa like the
Nautilus.
I have abridged my description of Canon
Moseley's investigations from Goodsir's " Ana-
tomical Memoirs/' edited by Sir .William
Turner (Edinburgh, 1868, vol. ii. p. 205 et
seq.); and I insert it here in order to lay
stress upon the fact that if any particular
class of natural objects were to be chosen
by a student for the purposes of such a
mathematical and creative art as architecture,
the class of shells would be the most suitable,
inasmuch as they suggest with particular
appropriateness those structural and mathe-
matical problems which a builder so often
has to face. The deductions made by
Professor Goodsir from Canon Moseley's
investigations will be mentioned later on in
their proper place. It will be appropriate,
however, to point out here that M. Vial de
Saint-Bel, a famous veterinary surgeon and
anatomist of the eighteenth century, made
very careful examinations and mathematical
measurements of the body and skeleton of
Eclipse, the famous racehorse which died in
1789. From these a valuable series of
standards and proportions was deduced,
128 THE NAUTILUS [chap.
which 1 have republished elsewhere1 as a
method for comparing the developments of
the English thoroughbred in the past hundred
years, and as some explanation, from the
purely mathematical point of view, of a
speed which was entirely owing to Eclipse's
wonderful anatomical construction. The most
interesting result of M. de Saint-Bel's in-
vestigations has only recently appeared ; for
he proved by mathematics that Eclipse must
have made certain movements with his legs
which nobody could see. Only when in-
stantaneous photography was invented and
applied to horse-racing, did these movements
actually make their appearance in the
photograph of a galloping horse.
Having given an example of "biological
mathematics" before Moseley, I will add an
example of mathematical biology after his
time, from the "First Study of Natural
Selection in Clausilia laminata (Montagu),"
which was published in October 1901, by
Professor W. F. R. Weldon in BiometriJca.
He pointed out that the problems presented
by certain terrestrial mollusca in Europe are
of great interest in connection with the theory
of natural selection, and that such specific
(though apparently "useless") characters as
1 " A History of the English Turf (Illustrated). Messrs
H. Virtue & Co,
vil] CLAUSILIA LAMINATA 129
the shape of the spire, the number of ridges
and furrows on a given whorl, or the size and
shape of the aperture, can often be expressed
in such a way as " to admit of numerical com-
parison between individuals/' The shell of an
adult Clausilia laminata is essentially a tube
coiled round an axis so that the successive
coils are in contact, much as in Turritella
lentiginosa ; and by carefully determining the
pitch and measurements of both the peripheral
spiral and the columellar spiral in a number
of examples from the beechwoods of
Gremsmuhlen in Eastern Holstein, Professor
Weldon drew various conclusions. The
upper whorls of the adult shell, he found,
represent the condition of the young shell,
from which this adult was formed by the
addition of new material, in a practically un-
altered form. Specimens taken from a
district which the species is known to have
inhabited since pre-glacial ages are in such
equilibrium with their surroundings that the
mean character of the shell-spiral is the same
from generation to generation, and is not
being changed by selection during the growth
of a young generation. The life or death of
an individual is in fact determined in each case
by the value of a number of correlated
characters, among which differences of
structure so slight as that of the measurements
i
ISO THE NAUTILUS [chap.
of the spirals are associated with the difference
between the survival and the total extinction
of a race in a particular locality.
The discovery of Neptune by Adams and
Le Verrier, owing to the calculations in-
volved by the observed aberrations of Uranus,
is an instance of " scientific thought "
well-known to astronomers. But another
example is quoted by Professor W. K.
Clifford, which is even more typical of the
mental process to which I desire to draw
attention. A dot on paper seen through
Iceland spar shows as not one but two
dots. Sir William Rowan Hamilton, late
Astronomer Royal of Ireland, knowing both
this phenomenon and Fresnel's explanation of
it, predicted that by looking through certain
crystals in a certain direction we should see a
continuous circle, and Mr Lloyd did see this
circle. On page 154 I have given a remark-
able instance of similar foresight in Leonardo
himself.
From the fact that some acids and salts,
when seen by a ray of polarised light,1 show
spirals which turn either to the right or left,
1 " Airy's spirals" is the name given to the peculiar
coloured interference-figures seen when two sections of
quartz, one of a right-handed, the other of a left-handed
crystal, both cut transversely to the vertical axis, are
placed one over the other, and viewed in converging
polarised light,
vil] PASTEUR 131
modern investigators have been inclined to
take the occurrence of this formation as a test
between organic and inorganic matter in the
long argument as to the possibility of breaking
down the distinction of vital force which is
supposed to exist between the thing that has
been " naturally " created, and the thing which
is "chemically made." In his laboratory a
chemist can now make a compound, such as
tartaric acid, which will be optically neutral,
that is to say, it will exhibit a mixture of
right-handed and of left-handed spirals, where-
as in Nature we find these spirals are of one
kind, either right-handed or left-handed in
each case. In the laboratory the one kind
can be separated from the other by biological
means, for there is an organism which feeds
upon one sort and rejects the other. Pasteur,
however, devised a process by which no such
biological assistance was necessary; for by
crystallising the compound he was able to
pick out those salt-crystals with their hemi-
hedral face to the right from others which
exhibited the left-handed formation. In
this way he approached very near the
boundary which still guards the mysteries of
organic life ; and it was the spiral formation
which enabled him to do so.
CHAPTER VIII
OF MASONRY
"The stairs as he treads on them kiss his feet."
TN previous pages I have attempted to give
some explanation of the beautiful spiral
lines upon the columella of such a shell as
that shown in fig. 53, which is the fourth in
a series of which Telescopium telescopium with
its single spiral (fig. 27) is the beginning. In
fig. 28 I reproduce the photograph of an old
staircase in the Chateau of Blois, built long
before Leonardo da Vinci came to France.
The origin of the architectural lines in such
a staircase as this is more easily explained
than the structure either of a Telescopium or
of a Voluta.
When the first great square or circular
feudal fortresses or keeps were built, the walls
were of such enormous thickness that the
space for the living rooms was very consider-
ably curtailed, and a staircase after the usual
London pattern would have left hardly any
132
M
chap, viil] LONDON STAIRCASES 13S
room at all either for the owner's family or for
his garrison. Yet it was necessary to get access
quickly and easily — in some cases secretly —
from one floor to another; and when a lady
was living in the same building with a number
of soldiers, she might desire, even in those
rough times when dignity counted for more
than decency, to have a separate staircase to
herself, leading perhaps from her boudoir to the
dais of the hall, while a different stairway, at
the opposite angle of the room, admitted the
crowd of men-at-arms who sat below the salt.
To manage these separate approaches by means
of two " London staircases " would have meant
a waste of room even more fatal than our own
modern cramped arrangements. The problem
was first solved, I imagine, by providing a
shaft in the thickness of the wall from one
floor to another, the entrances of which opened
in the corner of each room. But it would be
impossible to drop a man down this shaft like
a parcel, still less to climb up without help ;
and a ladder, whether of wood or rope, would
necessarily be at a dangerously acute angle.
So they began by inserting a brick at the bot-
tom of a shaft, just where my piece of string
was attached to the base of the cylinder in
my first illustration (see fig. 3) of an upward
dextral helix ; only you must now imagine
that the cylinder has become a long hole in a
134 OF MASONRY [chap.
solid body, and that into this containing circu-
lar body a slab of stone large enough to tread
upon has been placed a foot above the floor.
Continuing your natural spiral movement to
the right, you must then place another stone
in position, a foot higher than the other, and
further forward — that is to say, further round
this internal shaft up which you wish to ascend.
Continuing in this way, you will gradually fix
your slabs of stone to the inside of the shaft in
constantly ascending spiral curves until you
reach the top ; and with a little practice you
will be able so to adjust the angle of the spiral
that the end of it exactly reaches the upper door-
way. The wall will always be on your right
as some support, but there is a dismal cavity
on the left hand, and a false step would hurl
you headlong through the middle of the brick-
bristling shaft to the bottom. To avoid this,
in your next experiment you take rather longer
slabs of stone and diminish the danger ; but a
time arrives when you cannot increase their
length, owing to the fact that, though one end
is firmly inserted in the wall, the other stretches
out into emptiness, and a heavy weight might
entirely displace it. This would have been a
critical moment for the builder whose shaft was
of a large diameter.
When Charles V. of France built the grand
staircase of the Louvre (since destroyed), Ray-
viii.] THE STEPS TO HELL 135
mond du Temple found that the Paris quarries
of 1365 could not furnish big enough slabs in
time, for over six feet in length was what he
needed. So a selection of tombstones from
the Churchyard of the Innocents was made ;
and I can conceive no stranger material than
this "derangement of epitaphs." Surely the
Devil upon Notre Dame must have chuckled ;
for of what else are made the steps which lead
to Hell, even if the paving-stones are — on good
authority— of a different substance ?
But as the first of these primitive connecting
shafts was probably quite small, I think the
true solution of the whole problem rapidly
made its appearance. In the case of a shaft,
for instance, of six feet in diameter, if all the
slabs of stepping stones projected 3 ft. 6 in.
from the wall they would overlap. The first
case of overlapping may have been an accident ;
but, at any rate, it was soon found that this
method entirely covered up that dangerous
hole in the middle which I mentioned ; and
as soon as this was effected the greatest dis-
covery of all came simultaneously to light.
For as the stairway rose, a central column was
seen to be rising with it on the left hand of
any person ascending the dextral helix of the
stairs ; and by degrees the masons learned so
to cut their stepping-stones that this central
column was not only built up by these stones,
136 OF MASONRY [chap.
but also in its turn supported them, for they
now overlapped both at their ends and at their
edges. And now at last the outer wall on the
right-hand side fell into its true position of a
mere protective shell, while the essential feature
of the whole was the central column round
which the fan-like steps revolved.1
To explain this first development of the real
spiral staircase (instances of w^hich may be
found in most lighthouses and in the Tower
of London), I reproduce here a drawing by
Viollet-le-Duc, which shows one entire revolu-
tion of the steps, and also gives the drawing
(fig. 39) of a single step which contains its
own portion of the central pillar, as will be
found to be the case in the example I repro-
duced (in fig. 21) of the Palazzo Contarini.
It will be noticed that the architect has not
1 This explanation of the way a spiral staircase- was
evolved has high authority, and is accepted as possible
in such valuable text-books as the " Century Dictionary,' '
s.v. "Newel, . . . "in stairs where the steps are merely
pinned into the wall by their outer ends, and there is
no central pillar, the staircase is said to have an open
newel." But it is only right to state here that some modern
architects refuse to believe that any workman would pin
a step into the outer wall without supporting it by a beam
from beneath, and this is quite a probable deduction from
the character and methods of modern masonry. I have
been dealing, however, with the masons of a far older and
more independent period, and I incline to the belief that
the explanation given above is correct.
VIII.]
THE HANDRAIL
137
yet reached the idea of a handrail, and is
merely producing the simplest necessity for
internal communication without any idea of
decorative effect. Some kind of handrail for
the left hand soon became
necessary, and the first
was probably a rope which
was firmly attached to an
iron ring at the top of
the stairway and followed
its curves down to the
bottom, being kept atB
the right height by an
occasional staple on the
way. By degrees the
stone of the central
column got worn into a
regular groove by the
constant pressure of this
rope, and it soon became
evident that the handrail
might become not merely
an integral part of the
stonework of the staircase
but a very definite addition to the beauty of its
decoration. Such spiral staircases were known
to the Romans, who left the rough screws they
filed out among the ashes of Pompeii, though
they had not advanced sufficiently in mechanics
to be able to make a nut that would actually
A B
Fig. 39.
Primitive Spiral Staircase, with
plan of one step.
138 OF MASONRY [chap.
correspond. But the conditions of mediaeval
life made spiral staircases peculiarly valuable to
the feudal architect, for doors could open into
them at any height in their spiral upward
course ; they were easily lighted, and, at first,
of simple and rapid construction, which could
be easily repaired. They could be held by a
few men against a hundred foes ; they joined the
very top of the building with the very bottom,
and the slope of their ascent could be made
gentle or steep at will.
We have, of course, long ago rejected
such useful and beautiful possibilities in
London houses, which are as narrow and
lofty as a feudal keep, perhaps because we
could not easily get our furniture and other
cumbrous living-apparatus up and down a
spiral; yet, with these methods, it would
be possible to construct two interior spirals
where there is now scarce room for one narrow
stairway and a set of useless landings. The
danger of fire would certainly be reduced if
one of these spirals were constructed of unin-
flammable materials, or even built outside the
main walls of the building. At Hertford
College, Oxford, the architect seems to have
remembered a sixteenth-century model, but
to have been unable to find workmen capable
of carrying out a sixteenth-century design.
At any rate, the result is a somewhat inelegant
viil] TOWER HOUSES 139
compromise between the old and new. One
of the largest " Newel - Staircases " in the
United Kingdom is at Fyvie, in Scotland.
It is strange that the daily use of this
beautiful form of staircase is almost entirely
restricted (in the British Islands) to lighthouse
keepers ; for it is only found in towers, and
dwellers in the Martello Towers along the
coast are rare. The Border " Peels " were
built only for defence, as were probably Dacre
Castle, in Cumberland, or Belsay, in Northum-
berland. In Ireland the form survived much
later. In the old part of Blarney Castle, the
stone used does not contain the full circle
shown at " A," in fig 39, but only a half circle,
with the result that the columns in the centre
of each stair are only semi-cylindrical, and
exhibit one flat surface. But a very curious
fact I observed, there, is that throughout this
old part of Blarney, every staircase without
exception is sinistral in form, which shows that
Cormack McCarthy, the Strong, fully appre-
ciated the advantages involved in having his
own right hand free to attack an ascending foe
who would only be able to use his left hand
in defence. There is a spiral staircase in the
stronghold of the Black Douglas, Tantallon
Castle, near North Berwick, and this also is
sinistral, which may be for the same military
reason as that suggested at Blarney.
140 OF MASONRY [chap.
As the country became more settled, the
tower which was first used simply for safety,
was gradually built for pleasure too, as was
Nunney Castle, in Somersetshire, or Friston
Tower, near Ipswich, or Middleton Tower,
near Lynn in Norfolk, which is of brick, and
still (I believe) inhabited. But by far
the most interesting structure of the kind, also
of brick, which I have heard of in this country
is Tattershall Castle, in Lincolnshire, which
was designed by no less a person than William
of Waynflete, Bishop of Winchester, x for
Ralph, Lord Cromwell, Lord Treasurer of
England from 1433 to 1443, who built a
stately house for himself in his own country,
just as Chenonceaux or Azay le Rideau were
built by Financier - Generals of France.
Apparently his family had no connection with
the ancestors of Thomas, " malleus mona-
chorum," or of the still more famous Oliver,
both of the same name. Many of the fire-
places in the present House of Commons were
modelled after the magnificent specimens at
Tattershall, but the feature of the place which
I now wish to emphasize is the grand staircase of
one hundred and seventy-five steps, which is in
the South East Turret, and gives communication
1 See the Note on Tattershall Castle by Dr E. Mansel
Sympson, in "Lincolnshire Notes and Queries/' for April
1900.
viil] OPEN STAIRCASES 141
to forty-eight separate apartments, four of which
are very large. Its stone handrail, sunk into
the brickwork, and beautifully moulded to afford
a firm hand-grasp, is original in conception, and
probably unique in design. This is the only
staircase in a building eighty- seven feet long,
sixty-nine feet wide, and one hundred and twelve
feet high, which is almost entirely constructed
of small and brilliantly coloured bricks from
Flanders, or, as some think, from Holland.
The curve of this splendid staircase is of the
rare sinistral formation, and is contained within
a shaft twenty-two feet in diameter, built of
enormously thick walls.
It was soon found that spiral staircases
could not only be built into the interior of
a house, as in the example at Blois already
quoted (fig. 28), but that there was a distinct
gain both in freedom of access and in methods
of lighting when the whole staircase was placed
outside the walls, which thus secured an
admirable additional adornment, as is the
case in the " Escalier a jour " of the newer
wing of Francis I. at the same chateau (fig.
58). By the time this idea was realised, the
architect had made a very distinct advance,
and the mason who built for him had attained
a skill which is completely lost in his profession
nowadays. The delicacy of measurement
implied, for instance, in the single stone and in
142
OF MASONRY
[chap.
the completed spiral of the next stairway I
reproduce from Viollet-le-Duc (see fig. 40),
can scarcely be appreciated by any one who
has not endeavoured to do what is here
accomplished. For it
will be observed that
each step is light yet
strong, and carries with
it not only the central
spiral but the handrail
Ilk. b Ji| as well, while the con-
struction is so artfully
managed that the
solid central column
becomes lighter and
stronger as a hollow
cylinder, and, though
every step is firmly
balanced in its place,
yet a stone dropped
from the top of this
staircase would fall to
the bottom without
touching anything.
The beautiful possibilities of this method of
construction were in fact soon discovered, and,
as is so often the case in other matters, men
went to extremes of geometrical enthusiasm
which would be the despair of modern work-
men. This may partly be explained by the
B
Fig. 40.
Elaborate Spiral Staircase, with plan
of improved stonework.
Fig. 41.
Two floors of the Chateau of Charabord, showing the interlacing Spirals of the
Double Staircase. [To face page 143.
viil] CHAMBORD 143
fact that life in a feudal castle must have been
very dull at best, and a tricky staircase like the
one just mentioned may have been a godsend.
Not enough of them are still in existence for
me to give as many examples as I should like ;
but at Chambord, in Touraine, there is still a
tour de force in the way of spiral staircases
which would be very difficult to beat (see fig.
41). It contains two spirals, one within the
other, so arranged that a man may ascend from
the bottom, while the lady is tripping down-
wards from the top ; yet they will never meet
or see each other, though their steps and voices
are perfectly audible. The thing is a delight
to generations and armies of tourists at the
present day, and the pleasure it gave the
courtiers of Francis I. in that Gargantuan
Abbey of Thelema, in which he combined
fortress, hunting-seat, and pleasure-palace,
after the dark days of Madrid, may better
be described in the pleasant tales of a
Brantome or the picturesque exaggerations of
a Rabelais. It is not my present purpose to
go more into detail concerning such jeux
d'esprit, for I am in search rather of the
beautiful in construction than of the merely
bizarre; but they serve to show some of the
possibilities of a spiral, and of the attractions
which it exerted upon a constructively imagi-
native mind. In the parallel which I am
144
OF MASONRY
[chap.
seeking between the lines of architectural
construction and the lines of Nature's work-
manship, the central column of a spiral stair-
case is an integral factor, and in
the older Blois staircase (fig. 28)
you will observe that the decora-
tion of this central pillar, and
the carving of the single spiral
line that forms its handrail, have
already reached a degree of
beauty which enhances the ex-
quisite masonry of the curved
flight of steps ; and the colon-
nettes carved upon its surface
give just the same pleasing
contrast that we noticed in the
" Prentice's Pillar " (fig. 4). This
style of decoration was in use
earlier still in the fifteenth
century, and, in the last illustra-
tion I shall borrow from Viollet-
le-Duc, the wooden shaft of
Fig. 42. the now vanished College de
Central Wooden Montaigu in Paris provides an
Kth^cK excellent example, not merely
de Montaigu. of ^ j^ of pjjj^ but of the
rare sinistral helix (see fig. 42). It is worth
observing, however, at this stage of our inquiry,
that while it was easier and more natural for a
right-handed architect to draw plans for a
viil] THE BEST STAIRCASE 145
staircase with a right-handed spiral, this
" leiotropic " formation is not invariably better ;
for a man ascending it and turning perpetually
to the left (see fig. 28) would always have his
right hand free to attack the defenders, and
the garrison coming down would expose their
left hands on the outside. A left-handed
spiral will fit into any place where a right-
handed spiral will go as a staircase, because a
door can be pierced at any point in its course,
and I think it is therefore probable that right-
handed spirals are more common in staircases
because architects are usually right-handed,
and "build up" more naturally in that forma-
tion, not because such spirals are structurally
more convenient.
Evolved architecturally somewhat after the
fashion I have roughly sketched, was the
staircase (fig. 28) already long in use at Blois
in that older wing of Louis XII., which
Leonardo da Vinci saw when he first
visited the chateau. I have now to try and
imagine with what thoughts he saw it, and
what effects it may have had upon his busy
and speculative mind at the moment when the
various problems were just being considered of
that new wing in the castle for which Francis
I. had ordered plans and drawings to be
submitted.
K
CHAPTER IX
THE EXILE *
" There are two Books from which I collect my Divinity ;
besides that written one of God, another of His
servant Nature, that universal and publick Manu-
script, that lies expans'd unto the Eyes of all : those
that never saw Him in the one, have discovered Him
in the other." —Sir Thomas Browne.
VI7ITH the circumstances of Leonardo's
* * sojourn in France I must not concern
myself too much, but something must be said.
Within the shadow of the lime-trees on the
terraced garden of Amboise (some 30 kilometres
down the Loire from Blois) there is set a bust
of the great Italian, and an epitaph upon the
tombstone near at hand painfully records that
underneath it are ashes "amongst which are
supposed to be the remains of Leonardo da
Vinci." It was at Amboise, at any rate, that
he died on May 2, 1519 ; and the myth of
those last moments in the arms of his royal
patron at Fontainebleau becomes as shadowy
and unreal as the artistic reputation of
146
CO
g
Li.
S3 ~
2 "8
"SO
.a ^
S3 "^
O g
H3
chap, ix.] ITALIAN TRAGEDIES 147
Francis I., a reputation which I have always
thought to be much exaggerated. That
miscellaneous grave is not calculated to
increase it.
Leonardo had certainly lived in the Loire
valley some time before June 1518, as a
letter from him exists of that date written
at Amboise ; and he may well have reached
there in the year before; for it was in 1516
that he crossed the Alps at the request of
Francis L, in order to live at the manor
house of Cloux. If he had taken more
thought of contemporary happenings, he
might perhaps have remembered that the
Loire valley was already full of sinister
recollections of two great Italians whom he
had formerly served — Ludovico Sforza, called
II Moro, and Caesar Borgia. After taking
Bayard prisoner at Milan, only to set him free
again, Ludovico had been betrayed to La
Tremouille by his Swiss mercenaries, and was
sent to the dungeons of Loches, where he
languished for nine years in a sunless subter-
ranean cavern before he died. The pitiful
frescoes and inscriptions left by II Moro in
his cell by the banks of the Indre were
still fresh when Leonardo first saw the great
towers of Amboise across the Loire, which are
shown in my frontispiece. At Blois, on the
same stream, at Chinon on the Vienne, the
148 THE EXILE [chap.
memories of Caesar Borgia were scarcely less
vivid; for it was at Blois that Caesar, who
was created Due de Valentinois as a reward
for the Papal consent to Louis XII. 's divorce
which he had brought to Chinon, had been
himself married to Charlotte d'Albret. The
French king made his triumphal entry into
Milan with his new ally in October 1499,
and saw there for the first time the fresco of
The Last Supper, and the statue of Francesco
Sforza. By 1501, their artist had been com-
pelled to leave Milan, owing to the catas-
trophe of II Moro, and was military engineer
to Caesar Borgia. But the career of that
extraordinary adventurer was not entirely
suitable to prolonged artistic patronage, and
when Francis I. was in his turn making a
triumphal entry into distracted Milan, in
October 1515, after the Victory of Marignano,
Leonardo was again there to hear another
French king's praises, and by December of
that same year he was preparing, with Fran-
cesco Melzi, to follow a new patron to an
unknown country in the last years of his
life.
His little manor, close to the castle and
town, is now called Clos-Luce, and has hardly
been changed since it was built by Etienne
de Loup, steward of Louis XI. It has never
sheltered so many famous visitors as when the
ix.] LEONARDO'S DEATH 149
great Italian lived there, and in it he probably
painted the St John the Baptist of the Louvre
Collection, besides making plans for a canal,
with locks, at the confluence of the Sauldre
and the Morantin.1 It is probable, too, that
his hydrographic map of the Loire and its
affluents, now in the Codice Atlantico of the
Ambrosian Library at Milan, was made during
this same sojourn at Cloux, of which so few
facts have been recorded.
His will was made in April 1519, though
the written date is 1518. He made his pupil
and faithful comrade, Francesco Melzi, his
sole executor, left him all his priceless memo-
randa, of which I have printed a specimen
page in fig. 48, and expressed the desire to
be buried in the Church of the Royal Chapter
of S. Florentin at Amboise. There he was
laid to rest, in the next month, in the cloister,
as is known from his burial certificate. The
church was destroyed in 1808, and the skull
found on its site by Mf Arsene Houssaye
cannot, it may be feared, be acknowledged as an
authentic relic ; though the two stones found
in 1863 by M. Houssaye at Cloux, marked
"LEO . . . INC . . /' seem a more likely
1 He also suggested connecting the Loire by an im-
mense canal with the Saone at Macon, in order to open
up a new route for commerce between the north and
south of Europe.
150 THE EXILE [chap.
indication of the great artist's actual presence.
King Francis I. was at St Germain-en-Laye
at the date of Leonardo's death, and does not
seem to have taken any notice of the occur-
rence. Descendants of Leonardo's father l are
still alive, and the successors of Maitre Boreau,
the Amboise Notary who drew up his will,
were carrying on the business there till
1885.
The certificate of Leonardo's burial shows
that he had been engaged not as the king's
painter only, but as " premier peintre et
ingenieur et architecte du Boy, mechanischien
d'estat." His genius was of so universal a
quality that I feel no necessity for proving
over again that he had turned his attention,
among many other studies, to those of archi-
tecture. The researches of J. P. Bichter pro-
duce more than sufficient evidence of this,
though no building has come down to us
which has yet been recognised and agreed to
have been built by him. " In peace-time,"
1 In Gaye's "Carteggio Inedito d'Artisti" (quoted by
E. M 'Curdy), the date of Leonardo's birth is proved to have
been 1452 in a list of the household of his grandfather,
Antonio da Vinci, made for taxing purposes in 1457,
which records "Leonardo, son of the above-mentioned
Ser Piero, illegitimate, son of him and of Caterina, now
the wife of Accatabriga di Piero del Vacca of Vinci, 5
years." Milanesi accepts this evidence in his edition of
Vasari.
ix.] ARCHITECTURE 151
he wrote to the Duke of Milan in 1490, " I
shall be of as much service to you as any one
in whatever concerns the construction of build-
ings " : about the same time the Vice- General
of the Carmelites writes to Isabella d'Este,
concerning Leonardo, that " his mathematical
studies have so drawn his tastes away from
painting that he will scarcely hold a brush,"
and Sabba da Castiglione says also that " when
he should have wholly consecrated himself to
painting, in which he would, no doubt, have
become another Apelles, he entirely sur-
rendered himself to the study of geometry,
architecture, and anatomy " ; and it is signifi-
cant that between 1472 and 1499 we find
many important buildings in Lomhardy by
unknown architects, which are so good that
the tradition of collaboration between Leon-
ardo and Bramante may well be true. At
Pavia Cathedral, and in the church of Santa
Maria delle Grazie at Milan, this tradition was
so strong that the corroboration of it lately
found in Leonardo's manuscripts, preserved in
Milan, was only to be expected.
By Baron Henry de Geymuller all the
known architectural studies and writings of
Leonardo have been collected, and among
them may be pointed out his design for
draining " Romolontino " (the Romorantin of
Francis I.) and his sketches for a new royal
152 THE EXILE [chap.
residence at Amboise, " with a moat 40 braccia
wide, and to the right of the castle a large
basin for jousting in boats."
Already the best minds of his day had tried
to grasp the problems of a proportion in archi-
tecture which should reflect the laws of con-
struction and growth exemplified throughout
organic life in Nature. Leonardo took up that
inquiry in his usual original and thorough
manner, and the investigations embodied in
my former chapters were all suggested by
materials in his manuscripts. He has left
sketches of columns with archivolts shaped
liked twisted cords, copied from interlacing
branches. He has left drawings of flowers,
such as Eglantine, or Cyclamen, of a delicate
tenderness (see fig. 48), that is only surpassed
by the loving accuracy with which he analyses
and depicts the growth and structure of trees
or of mountains ; accumulating this infinity of
observation not for its own sake merely, but
in order to combine, and to create afresh ;
to invent with knowledge, and to design
without disorder.
He studied deeply the strength and resisting-
power of various materials, and was the first to
produce an exhaustive theory of the fissures in
walls. In fig. 44 I reproduce a careful study of
the spiral forms of smoke and dust caused by the
ruin of a building. He wrote much upon the
«,
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—
IX.] ANATOMY 153
nature of the arch, and the results of pressure
upon it. There was no problem of construc-
tion that came within his ken which he did
not grapple and attempt to solve. The traffic
in a crowded city was a difficulty in Italy long
before London had become overgrown. He
proposed to solve it with a system of high and
low-level streets, such as may be seen to-day
at Chester, and as has been suggested in these
last months for the new streets near the
Strand.
His notes and drawings of anatomy were
highly praised by so great an authority as
William Hunter, and the downward stroke of
a bird's wing, which is supposed to be so new
a revelation of the instantaneous camera, was
noted independently by Leonardo, as it had
been drawrn by the quick-sighted Japanese of
his own time. He observed, too, that as the
tips of a bird's wings in flight go up and
down as well as onwards, they make a spiral
in the air (fig. 45) which is adapted to the
strength of wind-resistance it has to encounter ;
and he made use of this observation in his
theory of flying machines. But in this figure
it should be observed that if the straight
line between a and p is the direction of
the body of the bird in flight, its wing-tips
would be approximately on a cylinder whose
axis was ap and radius the length of a wing ;
154 THE EXILE [chap.
so that a more correct description would be
that the movement of each wing-tip in flight
describes a line of which each portion is a
portion of a spiral, though the whole line so
described is not a spiral. But his keen obser-
vation of a bird's wings has received a much
more striking confirmation. His brain was
able to infer what no human eye could really
see, and when he noted that the spiral formation
of a screw was suggested by the movement
of a flying bird, it was not till four hundred
years afterwards that the truth of the infer-
ence could be visibly demonstrated.1 But in
Pearsons Magazine for May 1902, on page 506,
appeared one of Professor Marey's photographs
of a flying pigeon. I have reproduced it in
fig. 46, and the astonishing accuracy of
Leonardo's eyesight and observation may
easily be verified by a consideration of the
results produced by an instantaneous camera.
The prophecy he made so confidently still
awaits its fulfilment, but he did much to render
that fulfilment possible. "Pigliera il primo
volo," he cried, " il grande ucello sopra del
dosso del suo magnoCecero,empiendo l'universo
del stupore, empiendo di sua fama tutte le
scritture, e gloria eterna al nido dove nacque."
His Essay on Flight is throughout of the
1 Compare M. Vial de Saint-Bel's argument concerning a
galloping horse and its confirmation, on page 128.
o
LL
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Fig. 47.
A Page of Leonardo's Handwriting. (From Leonardo's ''Manuscript Note-book
on the Flight of Birds. ' )
II predetto uccello sidebbe coll' aiuto del vento leva-
-re ingrande alteza, e cquesta sia la sua sicurta ; perch6
anchora che l'intervenissi tutte l'anti dette revoluzioni,
esso a tenpo a ritornare nel sito dell' equalita pur-
-ch& le sua membra sieno di grande resistenzia, acc6
che possin sicura mente resistere al furore e impe-
-to del discenso, colli anti detti ripari, e le sue
giuuture di forte mascherecci, e li sua nervi di cor-
de di seta cruda fortissima ; e non si inpacci alcono
con ferramenti, perchfe presto si schiantano nelle lor tor-
-ture, o si consumano, per la qual cosa non b da'npacciar-
-si con loro.
The bird above mentioned should, with the help of the
wind, raise itself to a great height, and this will be its
safety ; because, although all the revolutions mentioned
may happen, there is time for it to recover its equili-
brium, provided its various parts are capable of strong
resistance so that they may safely withstand the fury
and impetus of the descent, being provided with the
safeguards mentioned, with their ligaments of strong
tanned leather, and their tendons of very strong raw
silk ; and no one need trouble to use iron joints,
because they split under the strain of a twist, or wear
out, so that there is no need to trouble about making
them.
Transcription by Giovanni Piumati, and an English Version of the
Translation by Charles Ravaisson Mollien. [To face page 155.
ix.] ON FLIGHT 155
highest interest, and I gladly acknowledge the
debt which every reader will owe to the public
spirit of its owner and preserver, Mr Theodore
Sabachnikoff. The page I reproduce (fig. 47)
will serve at once to show the nature of
Leonardo's notes and handwriting, and to
indicate the kind of material he left behind
him.1
In the Windsor Collection of his drawings
there are careful studies of flowers, of grass
and reeds, showing the various spiral forma-
1 The Notebook on the " Flight of Birds " was written by
Leonardo da Vinci at Florence in March and April 1505,
and left by him in 1519 to Francesco Melzi, who died in 1570.
From Melzi's Villa of Vaprio it was stolen by Lelio Gavardi,
and finally given by Horace Melzi to Ambrosio Mazzenta of
Milan. From him it passed to Pompeo Leoni, friend to Philip
II. of Spain, and by his heir was sold to Galeazzo Arconati,
who gave it, on 21st January 1637, to the Ambrosian
Library in Milan, where its existence is recorded by
Balthasar Oltrocchi, between 1748 and 1797, and by
Bonsignori in 1791. All thirteen MSS. of Leonardo were
sent to Paris by Napoleon in 1796, the Codex Atlanticus to
the Bibliothfeque Nationale, the twelve others to the Institut
de France. In 1815 the Codex Atlanticus went back to
Milan, the rest remaining (by error) at the Institut,
where the existence of this Treatise on Flight is noted by
the Sub-Librarian in 1836. From there it was stolen by
Jacques Libri, as Lalannes and Bordier noted in 1848, and
was seen in Florence by Count J. Manzoni de Lugo in 1867,
who bought it at Libri's death in 1868, and died himself in
1889. In 1892 it was bought by Theodore Sabachnikoff,
and published in Paris in 1893.
>
156 THE EXILE [chap.
tions of their growth (see fig. 48). Water,
and the forms of water, and of mountains,
seem to have attracted him very strongly,
as is suggested in the blue hills and streams
which are the background to "La Gioconda."
The Windsor Collection is full of extraordinary
studies of waves for his representation of the
Deluge. The great struggle of one element
against another did not appeal to him merely
as a Biblical dream. He examined currents,
whirlpools, and ripples, until he had a host of
actual facts with which to work; of true
observations from which to create his vision ;
of laws and principles by which to guide his
imagination. In fig. 49 a and b I have re-
produced two examples of the careful way in
which he studied the spiral formations of water.
It was for the gardens at the chateau of Blois
that he made sketches of further improvements
for the conduit, with its syphon discharging
into the Loire, which was built in 1505 by
Fra Giocondo, the Veronese architect. Among
his drawings are studies of the curves of waves,1
1 "The waves of light and sound," said the Italian, "are
governed by the same mechanical law as that governing
waves of water." Though the study of waves of light, or
sound, or nervous transmission, have yielded much more than
Leonardo dreamt to modern research, I know of no one who
has specialised so fruitfully upon the study of waves as Mr
Vaughan Cornish, whose work on " Kumatology '' stands
practically alone. He is now investigating all waves that
Fig. 48.
Study of the Growth of Flowers. By Leonardo da Vinci. (From the Windsor
Collection.) [To face page 156.
B
Fig. 49.
Study of the Spirals formed in Water. By Leonardo da Vinci. (From the Windsor
Collection.) [To face page 157 .
ix.] WAVES 157
and of the effects of currents upon the banks of
the mainland and of islands. In these studies
he foresaw the scientific advance which he had
no instruments delicate enough to prove, for
he wrote that : — " Le onde sonore e luminose
sono governate delle stesse leggi che governano
le onde delle acque" The water system
of the Cher and Loire he had thoroughly
worked out, and recorded in a map which
shows the relative position of Tours, Amboise,
Blois, Montrichard, and other places in Tour-
aine. In this connection, too, he frequently
expresses his admiration of Archimedes, and
of that great inventor's famous screw which
raised up water by the revolution of a pipe
twisted in a dextral helix round a rod.
I have already mentioned his particular
interest in shells, and in the study for the
head of his "Leda," which I reproduce in
fig. 43 at the head of this chapter, it is im-
possible to avoid the parallel between the
twisted coils of the Ammonite he knew (corn-
occur at the common surface of two bodies which move
relatively to one another, and his field is vast and fruitful,
for it contains such various subjects as the sand-dunes of
the Nile Delta, the ripple-marks on hills, the ice-folds of
glaciers, the waves of snow, of lava, and of air (created, for
instance, by a bullet), besides the waves in rivers, lakes, and
seas. The results of Mr Cornish's work, beautiful as they
are in themselves, will also have a most valuable indirect
bearing upon important and practical inventions.
158 THE* EXILE [chap.
pare fig. 36) and the spiral tresses into
which the woman's beautiful abundant hair
is plaited.1
He even investigated the structure of in-
testines, and it may be noticed that the draw-
ing in fig. 50 of the section of a shark's
intestine gives a peculiarly interesting example
of a dextral helix, the prime use of which is to
ensure that the food passes slowly round and
round the tube in order that every atom of
nourishment may be extracted.2 A very
beautiful parallel to this exists in the internal
formation of Auricula auris-midce (fig. 52),
and still more clearly in that of Turritella
lentiginosa (fig. 51), a shell in which you may
easily imagine yourself going up that " little
tower " on a continuous inclined plane without
any steps at all.
It is curious, to say the least of it, that
when Leonardo was living at Amboise there
existed a staircase built in the great tower by
1 In another manuscript he compares the spirals of a
woman's curls to the circling of a whirlpool.
2 The spirals occurring in intestines and other internal
organs are numerous, and will occur to every biologist. A
simple instance occurs in the ccecum of the rabbit (Lepus
cuniculus), one part of which, leading to the vermiform
appendix, is wide in calibre, diminishing somewhat towards
its termination, thin in its walls, and spirally constructed
externally in correspondence with the spiral valve developed
internally.
IX.]
INCLINED PLANES
159
Charles VI I L on exactly this model, and the
great round tower which contained it is shown
in Leonardo's drawing of Amboise which forms
the frontispiece to this volume.1 You might
drive a carriage and pair down its sloping
Fig. 50. Fig. 51.
Longitudinal Section of Turritella
Intestine of Raia. lentiginosa.
Fig. 52.
Auricula auris-midm.
circular curves to-day without meeting a
single step in all the distance; and the
Emperor Charles V. did, as a matter of fact,
ride up it on horseback by torchlight during
1 A visitor to Amboise would have to hold Leonardo's
sketch before a mirror in order to recognise that this tower
is drawn in its right place.
_
160 THE EXILE [chap.
one of his ceremonious visits to his rival
Francis I.
After all this, shall I be accused of too
much special pleading if I suggest that, to one
who had thus investigated the secret prin-
ciples of construction and of growth, and who
was especially attracted by the problems of
spiral formation, this inclined plane of the
spiral staircase at Amboise, and this single
helix of the old stair at Blois, presented a
greater attraction than that of merely archi-
tectural problems skilfully surmounted ? And
is it too much to infer that, for one who had
so carefully investigated the shells of Tuscany,
Lombardy, and Piedmont, the comparison of
the Amboise building to Turritella, and of
the Blois stair to Telescopium, was no im-
possibility? Those two Italian staircases
already mentioned, built by unknown artists
in Fiesole and Venice, are both of such a
period that, if Leonardo had ever studied
a shell in connection with the architectural
drawings for either, the names they both
bear may well be the popular recognition
of his skill in constructive adaptation. It is
interesting, too, to find that John Bellini's
Allegory of the Shell (p. 51), was painted
for the Contarini family, and that their Scala
del Bovolo has always been referred by tra-
dition to a French model, which is not
ix.] OLD AGE 161
without a certain suggestiveness as to the
investigations of the great Italian exile in
that valley of palaces which is Touraine.
In considering the possibility of such studies
in parallelism of structure having occupied
the leisure of a great designer, it will be only
natural to look for the evidences of any
practical result towards the end of a life
in which busy activity would for the most
part postpone such delicate imaginations until
increasing years had brought more oppor-
tunities of investigation and research. When
Leonardo reached Touraine he was nearing
the end of a life that had been crowded with
creative action. The full fruit of one of the
most strenuous and original careers ever known
was in the autumn of its ripeness. Many of
the problems which that fertile brain attacked
have never yet been solved, and if I finally
trace to its marvellous inventiveness a
creation that no recorded architect has yet
been found worthy to claim, it is chiefly
because the beauty of that creation of man's
handiwork remains unparalleled outside the
realm of Nature.
As I approach this last portion of my
argument, I must again refer to that series
of internal spirals in shells which I mentioned
before, beginning with the single line of
Telescopium telescopium (fig. 27), or even
L
162 THE EXILE [chap.
further back with the mere inclined plane of
Turritella lentiginosa (fig. 51), and ending in
the eight-fold curves of Voluta musica (fig. 33).
In that series I wish now especially to
emphasize Voluta vespertilio (fig. 53) and the
four particularly graceful lines of its dextral
helix. But I must also point out the beautiful
lines observable in its external shape (fig. 56),
which are not quite parallel, yet satisfy the
eye completely in their gradual upward ascent.
You will notice, too, that the main external
walls of the shell are buttressed, as it were,
with little outstanding columns which hold
up the first of the ascending lines in a manner
that would be at once suggestive to an
architectural eye.
We have already observed, both at Venice
and at Chartres, the strange correspondence
between the exterior arrangement of a stair-
case and the external shape of a shell. At
Blois, in the old stairway, we have seen an
internal single spiral closely corresponding to
the internal single helix of the columella in a
shell. I have now to point out an archi-
tectural example which combines both these
correspondences, and does this although no one
who only looked upon the exterior of the
"Escalier a jour" at Blois (fig. 58) would
dream of what it contained within, any more
than a person ignorant of biology who looked
ix.] CLOSE RESEMBLANCES 163
at the outside of Voluta vespertilio could
imagine the existence of the quadruple helix
inside it. When it was only the outside, or
only the inside of a staircase that suggested
the lines of a shell, the evidence may not
have been sufficient to argue any connection
between the one and the other in the builder's
mind. But what if the external plan be the
same in both a staircase and a shell, and if the
internal spiral of the stair be an exact copy
of the columella within the same shell, even
to the number of its revolutions round the
shaft? And what if, in addition, these
arrangements are in each case carefully
reversed in every detail ?
CHAPTER X
THE SHELL OF LEONARDO
" Majestati Naturae Par Ingenium "
A T Blois there is a staircase built later than
^ the old example shown in fig. 28, built
just at a time when Leonardo's presence in
Touraine might have enabled him to suggest
its plan, built with its external lines
corresponding to the outside of a shell,
while its internal spiral reproduces the helix
on the columella of that shell.
In the known examples of Voluta vespertilio,
about one in a million contains a sinistral
helix instead of the ordinary dextral curve.
I have mentioned an instance where such a
rare shell at Travancore was considered to
have been a manifestation of the Deity. It is
therefore probable not only that travellers
would try to select one of this kind to bring
home, but also that in the case of shells
common on the seaboard of Italy, the chief
reason for the presence of one of them in the
164
Fig. 55.
Escalier a Jour, Chateau de Blois, Touraine. The Central Shaft.
[To face page 165.
CHAP. X.]
FORMS OP VOLUTA
165
cabinet of an Italian collector would be that
it was distinguished above its million fellows
by the possession of this rare sinistral helix.
Compare the Voluta in figs. 53 and 56 with
that shown in figs. 54 and 57, and in the two
latter instances you will see that the spirals
are reversed, that the " entrance " is on the
left instead of on the right, and that the
external lines slope down from left to right
Fig. 53.
The Common Form of Voluta
verpertilio (section).
Fig. 54.
Eare Form of Voluta
vespertilio (section).
instead of from right to left. Figs. 53
and 56 show the ordinary leiotropic shell
with a right-handed spiral. Figs. 54 and 57
show the rare dexiotropic shell with a sinistral
or left-handed spiral.
With this exceptional formation in your
mind, remembering also that the ordinary
166 THE SHELL OF LEONARDO [chap.
ascending curve described by a right-handed
man is to the right, compare the magnificent
spiral within the staircase of the wing of
Francis I. at Blois (fig. 55) with the helix
in the leiotropic Voluta vespertilio (fig. 53).
It is identical in form, even in the fact that it
is four times repeated, but it is reversed.
Fig. 56. Fig. 57.
Common Form of Voluta vespertilio. Rare Form of Voluta vespertilio.
Then compare the external balustrades
(fig. 58) with the lines on the outside of the
same shell (fig. 56). They are arranged in
the same way; they are similarly supported
by slender columns; they show the same
charming and curious irregularity, which
seems inexplicable apart from their model;
but they are reversed. Notice also that any
ordinary architect would have made the lines
Fig. 58.
Escalier a Jour, Chateau de Blois, Touraine. The Exterior.
{To face page 166.
x.] AGREEMENTS AND DIFFERENCES 167
of his external balustrades correspond with the
main external lines of the floors in the
building to which this open staircase was
added, if the designer of the internal stairway
had merely wished to build a four-fold spiral
round its central column. But the designer
of this staircase had not merely a quadruple
mathematical line in his mind, he was think-
ing of a shell ; and he was not thinking of
Cymbium, a shell which has four plaits on its
columella and an exterior quite different to
that shown in fig. 56, but of Voluta vespertilio,
which hides its quadruple helix behind an
arrangement of sloping lines growing above
slender columns, exactly as these sloping
balustrades are built.
Look finally at the doorway opening to
the staircase from outside. It is in the same
relative position as the "entrance" of the
shell ; but it is reversed.
There are therefore no less than four
instances of agreement with the common
shell, though in any one of these four a
trifling difference would not have mattered to
the construction. And in all these four
instances there is an invariable and exact
reversal, although again there might have been
trifling variations in plan made by any one
who had not got the shell before him.
Can such agreements and such differences
168 THE SHELL OF LEONARDO [chap.
be chance alone? Can such lines be the
result of a merely architectural solution of
the problem? Can they be merely one more
example of what we have seen already, of
the fortuitous correspondence between perfect
workmanship and the lines of Nature ?
Surely they must be a deliberate copy of the
natural object they so closely imitate ; yet
not an ordinary copy, but a copy with the
very striking and logical and persistent
differences we have just noticed.
This, in fact, must be an example of that
greatest art which imitates the greatest models
with a difference that reveals the strength
and personality of the designer; which
discards the trivial and preserves the essen-
tial ; which loves knowledge much, and is
therefore unafraid of novelty ; which realises
the existence and the value of a studied excep-
tion here and there among all ordered things ;
which can unite design with fact, and
originality with truthfulness ; which has, in
fact, discovered that the beauty of Nature is
not to be found in agreement, but in
difference.
Such a creation as this might well have been
one of the few practical results of that philo-
sophy which was expressed in the words :
"Natural things are finite, but man's handi-
work is infinite " ; a saying which was not likely
x.] NATURE IS FINITE 169
to have been uttered by one who could have
permitted many such works to survive him.
For this man had realised that in the per-
fection of Nature there is an end attained, un-
changing, because perfect in its kind ; but that
we are " something better than the birds or
bees," and in our best building, as in our best
art, the confession of that superiority must
always be found. Hence comes that nobler
love of change which is the divine unrest of
genius, which often leaves so little done behind
it, because there is always so much still to do.
Some faint suggestion of this feeling is to be
found in the expression on the face of " Mona
Lisa." Not of any mortal handiwork were the
words written, " Behold, it was very good " ; for
labouring humanity is driven forward through
the ages by the constant search for something
higher that is ever hidden, yet ever to be
revealed.
If then, as 1 believe, this staircase was copied
from a shell, the man who owned the shell and
used it so must have been not merely an archi-
tect but a master of construction, for the groin-
work and vaulting of the stairs (fig. 59) are
not the least astounding part of the whole
building ; and he must have been a decorative
artist, too, of the very highest order. Con-
fining your attention for a moment to the
inside of the staircase only (fig. 59), you will
no THE SHELL OF LEONARDO [chap.
see ample evidence of this in several directions.
The stairs wind upwards, folding round that
exquisite central shaft as the petals of a flower
fold one within the other; and in the very
lines of each step itself a strange and beautiful
look of life and growth is produced by the
double curve on which it is so subtly planned ;
for these steps are not straight, as in the older
staircase of the chateau, and in most ordinary
instances, but are carved into a sudden little
wave of outline just where each one springs
out from the supporting pillar — from the sup-
porting stalk, as it were, of these delicately
encircling leaves. Though I am more con-
cerned with constructive lines than with mere
decorative detail, it is impossible also to over-
look the set of these colonnettes that move
upwards with the rising shaft, and the splendidly
sculptural treatment of the shells which are set
between the twisted capitals of each (fig. 55).
I would draw particular attention to these,
because if they were placed here by the man
who was inspired to take his original model
from a shell, they would be treated very
differently from any ornaments subsequently
affixed by a lesser artist with a lesser inspira-
tion. And this is, as a matter of fact, exactly
what is to be found here. These shells are
broadly carved, with light and shadow; not
with a mere imitation of exact form, but with
Fig. 59.
Vaulting and steps of Spiral Staircase in the wing of Francois I., Chateau de Blois.
[To face page 170.
x] SUBSEQUENT ADDITIONS 171
a fine feeling for their effect in this exact posi-
tion. Beneath them are weakly conventional
embroideries of later date, that are not merely
meaningless, but are cut off at the bottom by
the ascending spiral in a way which no one but
a sculptor devoid of all structural adaptability
could have permitted. They must be addi-
tions of about the same date as the statues set
upon the exterior some fifteen years after the
original structure had been built. They are
repeated in the rooms of Catherine de Medici
above, and may be seen, in exactly the same
setting, on the shaft of the great stairway of
Chateaudun, a structure so complicated with
archways and landings that the fine right-
handed spiral of the central column almost
loses its effect.
Yet it is the irresistible, spontaneous, uplift-
ing movement of the whole that remains, after
all, the main impression of this marvellous
piece of work at Blois. To walk up those
steps is to be borne along upon a breath of
beauty, and not to feel the clogging feet of
human clay at all. Those waving lines rush
upwards like a flame blown strongly from
beneath; for there is in them a touch of
that spell which is elemental ; of that same
Nature's mystery which curves the tall shaft
of the iris upwards from the pool in which
it grows, or flings the wave in curving lines
m THE SHELL OF LEONARDO [chap.
of foam upon the rocks the rising tide will
cover.
He who made all this, and who owned the
shell which first suggested it, must have been
an architect of powerful originality and an
artist of extraordinary imagination, with a
sense of harmonious proportion rarely equalled
in the world, a sense which he had trained
in many various arts and many branches of
science, for he must have been a student of
biology who collected natural objects with a
determination to penetrate the secret of their
beauty, just as one of the greatest of our
modern sculptors, Gilbert, has studied the
bony forms of fishes, and from them designed
the most exquisitely curved armour and the
most fantastically beautiful ornaments. Learn-
ing and taste so universal as this seems to
indicate have been rare at any period of the
world's history : between 1500 and 1519 there
was certainly but one man who possessed them,
and that was Leonardo, the artist, architect,
and biologist, who devoted so much of his life
to the study of the intercommunication Be-
tween art and nature ; who, in fact, did even
more in this direction in the fifteenth century
than Gilbert or any other artist did in the
nineteenth ; who gave this final manifestation
of his constructive genius to France's ungrate-
ful monarch just before he died ; who came
x.] VOLUTA NOT FRENCH 173
from those Mediterranean shores where Voluta
vespertilio (which is not a French shell) was
known.
Professor W. R. Dunstan, F.R.S., has been
kind enough to give me a Voluta from the
Barton Beds of the Eocene Age on the coast
of Hampshire, where there are a very large
number of these shells to be found in so re-
markable a state of preservation that they seem
scarcely fossilised at all. In the days of Leo-
nardo, and of course long before him, Voluta
had vanished, as a living form, from the Eng-
lish and French coasts and from all waters that
were colder than Italian seas. I have not re-
produced the English specimen, as it does
not advance my argument, though its lines are
even more beautiful than those of the Medi-
terranean shell known to Leonardo da Vinci.
His death occurred in May 1519, only some
twenty miles from Blois, at that Amboise
where he had been living for some time. The
first payments recorded for the new wing at
Blois containing this staircase were made by
Baron de Joursanvault in July 1516, just six
months after the French King had arranged
for Leonardo's departure from Milan. The
most cursory inspection of the plan of the
whole building will show that such an external
feature may well have been completed after
the main lines of the building had been laid.
174 THE SHELL OF LEONARDO [chap.
Its beauty is artfully thrown into relief by
the comparative simplicity of the wall from
which it springs. So perfect a whole as is the
staircase may well have taken many years to
finish, after Leonardo had given the first
masterly sketches of its plan. Some stones
in it have been left untouched until this day,
and a few are only roughly chiselled out.
Above and around the entrance are three
statues which are very characteristic of a
master of a much later period, Jean Goujon,
who was carving at Ecouen in 1544. His
help may well have been called in to put the
finishing touches to a structure which a greater
than he had originated. No subsequent adorn-
ments could alter or weaken the beauty of the
main conception.
The sinistral curve within it is rare in any
architecture, and, as I have pointed out, it is
an exact reversal of the spiral contained within
the ordinary Voluta. It would have suited
the internal and external arrangements of the
rest of the building just as well if the drawings
for this staircase had been made on the plan
of the ordinary dextral helix which is exhibited
in its simplest form in the staircase built at
Blois (fig. 18) before Leonardo came to
France. There is no constructive reason,
therefore, for the reversal, and a probable
reason for any designer putting a left-handed
PQ
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x.] LEFT-HANDED 175
spiral into his sketches would be that he was
himself left-handed.
Leonardo da Vinci was left-handed. Ninety
per cent, of the screws and spirals contained in
his manuscripts are left-handed spirals, and in
fig. 60 I have reproduced five of these out of
a great number similarly drawn.1
It may be urged that having made his first
rough sketch in the manner which came most
natural to him, the architect could easily have
changed it when once he had begun his work-
ing drawings. But Leonardo would not have
considered the problem in that light. He was
no mere slave to precedent. He had begun
by drawing the left-handed spiral which came
instinctively to the left-handed draughtsman.
It interested him to notice the difference from
the usual form, and he went on with his
rarer form deliberately, carefully investigating
whether it was better than the common style.
As we look at the turn of the steps now, we
realise that they move upward in the same
direction as the hands of a watch moves for-
ward as it lies upon a table, " through the
1 The fragments brought together on this plate show also
his habitual method of shading from left to right, and I
have given his right-handed signature in the same place in
order that it may be contrasted with the far firmer and
clearer writing done by his left hand on the opposite corner
of the plate.
176 THE SHELL OF LEONARDO [chap.
buttonhole," as they say in Lincolnshire. It
is after this manner, too, that fashion has
decreed we should deal a hand at cards, and
that superstition has ordered us to pass the
Port.1 In architecture also, this arrangement
produces an effect of hospitality in the curve,
for a host could walk down it with welcoming
right hand outstretched to the ascending guest,
who was in his turn helped on his ascent by
keeping his own right hand on the side-rail,
just as you may see the modern athlete keep
his right side inwards as he runs round
the track at Queen's Club. Certainly, also,
this stair is easier to walk up, a fact
which may be verified by practical experience
to-day.
Right-handed spirals are not only more
common in Nature, they occur more often
in art, because the average right - handed
1 In 1690 a new "Dictionary of the Canting Crew" was
published, in which the phrase " Catharpin-fashion " is de-
fined as follows : — " When People in Company Drink cross,
and not round about from the Right to the Left, or accord-
ing to the sun's motion." The word "withershins," or
" widdershins," also means against the sun (wither = against,
shins= sun's), and to go round a church from left to right (as
you face the chancel from within) was believed to give the
Devil power over so careless a traveller. The word may be
connected with wiederschein = to reflect, as in Virgil's de-
scription of the rainbow, "Mille trahit varios adverso sole
colores."
x] THE DEXIOTROPIC SHELL 177
architect had not cared to face the result
that they involved a continual turning to the
left; so he followed precedent, although on
a left-handed spiral a man turns easily and
naturally towards the right in his ascent. So
far, then, this new arrangement must have
satisfied Leonardo's practical sense of fitness.
But it involved carrying out the same idea of
reversal in its entirety, without the help of
any previous examples in the district to guide
him.
Certainly, if it was a shell before him of
which he was thus reversing both the internal
and external lines, he was the only architect
then living who might have done so with the
knowledge that Nature had, in one example
out of every million, done the same before
him. One of these rare examples he may
have possessed and used, but it is more prob-
able that he did not have before his eyes so
uncommon a dexiotropic Voluta as that which
I have reproduced in figs. 54 and 57 ; and if
he did not, this rare shell, shaped by some
left-handed angel of the Ocean, and worshipped
as the evidence of some supernatural presence,
becomes a triumphant vindication of his skill ;
for when its reversed lines are compared with
his staircase, they will be found exactly to
correspond in every case. Rare as the sinistral
single spiral is in architecture, Leonardo's par-
M
178 THE SHELL OF LEONARDO [chap.
ticular development of the fourfold sinistral
spiral is unique; and it is significant that
the double interlacing staircase built by
Pierre Trinqueau in 1526. close at hand
in Chambord (see fig. 41), is also of this
same rare sinistral form which had but just
previously been built by the Loire ; in tacit
acknowledgment, as it seems to me, that
no single stairway, even if it were similarly
reversed, could ever compete for sheer beauty
of construction with the older masterpiece at
Blois.
To Leonardo the revelation of spirality thus
so triumphantly manifested, its connection with
religious doctrines, and the value of its sym-
bolism, must strongly have appealed. As we
know, he investigated many of the forms
it took, and no doubt he knew far more
of them than I have indicated here. He
found it in such humble instances as the coil
of the worm, the curve of the snailshell, the
budding of the fern. Completed in the Ionic
capital, arrested at the bending-point of the
acanthus-leaf in the Corinthian, it became,
he saw, a primal element of architectural
ornament, eloquent with many meanings,
representing the power of his favourite
waves and winds in Greek building, typifying
the old Serpent of unending Sin in Gothic
workmanship.
x] THE MISTRESS-ART 179
For him science was the handmaid of the
imitative and creative arts, the tool by
which he gave reality to his imaginations.
His work was the healthy manifestation of a
strong and subtle intellect ; the mixture, and
the equipoise, of all that is best in the faculties
of man ; and this is why his creations show
that elusive quality of naturalism mingled with
the ideal, of analysis with emotion, of soul with
body. In him the artist and the scientist
dwelt harmoniously together, worked harmoni-
ously. No one of his time had observed so
keenly ; no one could express his observations
with a greater realism. But his art was no
mere servile form of imitation. He could
both imagine and create, because he had an
inexhaustible material from which to mould
fresh forms. " Non e creatore se non Iddio ed
il poeta " (" God and the poet are the only
creators") said Tasso. But only an intellect
so comprehensive as was Leonardo's could
have justified the greater saying : " Natural
Things are finite, but the works which the
Eye can order of the Hand are infinite. " One
such "work" of his creative imagination did
he reserve for the close of his life, and for
its expression he chose that " mistress-art,"
architecture, to which all the other arts he
knew are handmaids.
Again and again has the same search for
180 THE SHELL OF LEONARDO [chap.
the subtle and elusive causes of beauty been
taken up. It has attracted minds so different
as Hume, Bernouilli, Burke, and Winckel-
mann, among many others. Hogarth left us
his idea of it. Professor Goodsir adopted the
logarithmic spiral as a kind of teleological
chart in Nature's beautiful designs. Taking
Canon Moseley's investigations as his text, he
tried to illustrate their logical corollary that
the form and law of growth of an organic
body being known, its form at any future time
might be made a matter of mathematical
elucidation. Following out with astonishing
fidelity the line of investigation laid out by
Leonardo da Vinci three centuries before,
Professor Goodsir asked when it would be
possible, by ascertaining the accurate shape,
form, and proportion between the parts,
organs, and whole body of any animal, to
advance anatomical study geometrically. One
of his most enthusiastic disciples, D. R. Hay
(" On the Human Figure," 1849 ; " Natural
Principles of Beauty/' 1852 ; " The Science of
Beauty," 1856), examined the geometric out-
line of the human body, just as Leonardo
is said to have done when the Aphrodite of
Praxiteles was discovered, and produced a cer-
tain harmonic proportion, by following which
a correct anatomical outline could be drawn
from a mathematical diagram. What Goodsir
x.] THE CURVE OF GROWTH 181
sought for all his life was some physiological
law ruling the form and growth of organisms
as gravitation is held to prevail in the physical
world. If from the geometric curves of the
planets' orbits Newton deduced the law of
the force, said he, may we not learn " the law
of the force" in natural objects also when
we have got their mathematical forms ?
It may be very long before we do so,
because very few biologists are mathemati-
cians as well. But if ever this does come
to pass, Canon Moseley's paper will be taken
as the beginning of a new epoch in natural
science.
Professor Goodsir considered that biology
owed its progress to the study of final causes,
to the study of the remarkable adaptation
of structures to particular functions. This
is not the most fertile mode of procedure in
physical or chemical investigations, owing to
the difference between organised and in-
organised bodies. For each individual organ-
ism forms a system in which the reason why
its parts are adapted to each other may be
studied. But it is impossible to put the Solar
System under our eye and examine it in order
to explain the Sun. It is noticeable, however,
that Newton showed in his "Principia" that
if attraction had generally varied as the inverse
cube instead of as the inverse square of the
182 THE SHELL OF LEONARDO [chap.
distance, the heavenly bodies would revolve,
not in ellipses, but in logarithmic spirals,1
rapidly diffusing themselves and rushing off
into space. If therefore, asked Goodsir, the
law of the square is the law of attraction, is
the law of the cube2 the law of production,
and is the logarithmic spiral the manifestation
of the law which is at work in the increase
of organic bodies ?
The process by which such results as those
shown in the "Principia" must be reached
may be described as two steps, the first being
the hypothesis (based on the purely abstract
conception of perfect motion) that the motion
of a planet was like that of a ball swung on
the end of a string ; the second step is when
Science discards the hypothesis, and uses
it merely to investigate the properties of a
planet's motion. This is the process that has
been exemplified in the discovery of the law
of light and heat, or in the hypothesis which
is based upon the abstract conception of a
perfect liquid. Clearly, there can be no
1 It is worth considering in this connection that the
growth of systems seems to be expressed in the spiral
nebulae discovered by Lord Rosse, as opposed to the
circling of completed weights in the case of perfect planets
which follow a fixed orbit, owing to the unvarying law
of gravity.
2 " The law of the cube," that is, the law of the cell
also.
x] CHURCH'S THEORY 183
objection, as Mr Church points out, to the
application of a mathematical conception in
itself either to phyllotaxis and the arrange-
ment of leaves upon a stalk, or to conchology
and the growth of the Nautilus. Everything
in nature is capable of mathematical expression
if the conditions are only sufficiently well
known ; the real difficulty is to select a
fundamental conception which will admit of
modification when new factors are introduced.
In other words, if the genetic spiral be regarded
mathematically as winding to infinity, and
being engaged in the production of similar mem-
bers, it can only be represented by the loga-
rithmic spiral which makes equal angles with
all radii vectores. " Eadem mutata resurgit."
This spiral, representing the laws of mathe-
matical asymmetrical growth around a point,
constitutes in Hydro-Dynamics the curves
of spiral- vortex movement, and its application
to magnetism has been fully investigated by
Clerk Maxwell.
From this last point Mr Church is now
working towards the proof of a hypothesis
which he has not fully published ; but he
clearly thinks that the distribution of living
energy follows identical lines with those of
electrical energy, for example, and that a
phyllotaxis diagram, or (as I should add) the
plan of a Nautilus, is comparable to electrical
184 THE SHELL OF LEONARDO [chap.
lines of equipotential.1 The theory, if correct,
would be fundamental for all forms of growth,
though it could be more easily observed in
plant-protoplasm than in animals.2
1 If this hypothesis be correct, it may form a very im-
portant factor in such experiments as those reported by
Mr A. B. Plowman in the Harvard Botanic Garden, on the
relations of electricity to plant-growth, or in such researches
as those of Professor Lemstrom of Helsingfors.
2 Mr Church's further statements, being somewhat too
technical for the ordinary reader, though of extreme
importance to the theory mentioned above, are here quoted
in a footnote from his " Note on Phyllotaxis " (1901).
" The possibility that the contact parastichies may be
also not only log-spirals but log-spirals which intersect
orthogonally, and thus plot out a field of distribution of
energy along orthogonally intersecting paths of equal
action, is so clearly suggested that it may at once be
taken as the groundwork of a theory of phyllotaxis more in
accordance with modern lines of thought. ... It is
difficult to avoid the conclusion that the logarithmic spiral
construction gives the true key to the problem, and that
the whole subject thus becomes a question of the
mechanical distribution of energy within the substance of
the protoplasmic mass of the plant-apex : that phyllotaxis
phenomena are the result of inherent properties of
protoplasm, the energy of life being in fact distributed
according to the laws which govern the distribution of
energy in any other form : and that the original orthogonal
planes, the relics of which survive in the contact
parastichies of the system, represent the natural con-
sequence of a mechanical system of energy-distribution
directly comparable with that which produces the ortho-
gonal intersection of cell-walls at the moment of their first
formation." . . . "The logarithmic spiral theory," he
x.] THE UNKNOWN FACTOR 185
It will be seen that, in all efforts to define
a natural object in mathematical terms, we
come to a point at which our knowledge of
the involved factors ceases. The Nautilus is
almost a logarithmic spiral, but not quite.
Nor can a phyllotaxis diagram, as Mr Church
admits, ever show that the plant's growth is
mathematically correct. All that can be said
is that the logarithmic spiral is as near as we
can get in mathematics to an accurate de-
finition of the natural phenomena. To this
same stopping-place the mathematician is also
brought when he tries to express beauty in
terms of measurement. In other words, the
baffling factor in a natural object is its life,
its organic growth. The baffling factor in
a masterpiece of creative art is its beauty, a
quality as essential and as intangible as life.
This means therefore that growth cannot be
wholly expressed by algebra or trigonometry,
concludes, " is so far then the logical outcome of Sachs*
theory of the orthogonal intersection of cell-walls, and
represents therefore another special case of the distribution
of energy along planes of ' equipotential.' "
The symbolism of the spiral form of ornament originally
taken from the lotus (see p. 49) therefore receives a striking
confirmation of its power and meaning; and the occurrence
of the logarithmic spiral in such minute organisms as the
microscopic Stentor coeruleus indicates how widely this mar-
vellous curve can be applied to a consideration of living
growth (p. 73).
186 THE SHELL OF LEONARDO [chap.
though these may help us to appreciate and
describe the phenomena we examine. It
means also that a thing constructed merely by
rule and thumb and mathematics must
inevitably fall short of perfect beauty. For
perfect beauty, like natural growth, implies
irregular and subtle variations.
By this path we may perhaps reach some
more intelligible explanation of that vague
but most important quality — "good taste."
It is born in some men and unknown by
others. It can be widely distributed, or the
life of ancient Hellas becomes an unintelligible
miracle. It can be lost in just as large a
measure, or most modern architecture would
be a nightmare, from which our waking
moments would be free. It has a definite
relation to, and a keen sympathy with, the
phenomena of life and growth ; so it must
to some extent partake of their qualities.
A man whose vitality is strong, whether it
be physical or intellectual, would therefore
be likely to possess it, if he were keenly in
touch with Nature, if he abhorred artificial
rules, and mathematical or mechanical results.
This would explain both its general prevalence
in ancient Hellas, and its general absence in
an age wThen machine-made productions have
become paramount ; when designers trust to
mathematics ; when the public object to any-
x.] THE IONIC VOLUTE 187
thing but repetition. One of the chief mani-
festations of "good taste/' then, is the
appreciation of the truth that beauty, like
life and growth, depends not on exact copy-
ing, but on those subtle variations to which
the scheme of creation, as we know it, owes
those great laws of the origin of species and
the survival of the fittest.
A good architectural example of this de-
liberate and subtle variation, which was the
Greek ideal of beauty, may be found in the
volute of an Ionic capital. It is no more
mathematically correct than the lines of the
Parthenon are mathematically straight. It
is beautiful because it exhibits just those
variations which are observable in organic
growth.
The ordinary method of drawing a " correct "
volute with the help of an inverted cone is, of
course, well known, and results in a mathe-
matically exact and aesthetically vapid figure.
But Mr Banister F. Fletcher (in the Building
News for 22nd August 1902, p. 247) has
shown that a shell can be used for the same
purpose (fig. 61). Following his instructions,
I took the sinistral whelk mentioned on page
90, and wound a piece of tape, 12 inches long,
round its spirals from its apex (E) to the top
of the opening, leaving a little of the tape over
to hold the rest in position. A pencil was
188 THE SHELL OF LEONARDO [chap.
attached to the end of the tape touching the
apex. Reversing the shell so that it stood
perpendicularly upon its apex at the point
marked E in the diagram of the volute, and
keeping it fixed on that point, I drew the
pencil round and round the shell in the gradu-
ally increasing curves permitted me by the
gradual unwinding of the string. The volute
reproduced in fig. 61 is the result. The shell
used was exactly contained in a rectangular
space 4r^ inches long by 2\ inches wide. It
produced a spiral measuring lOf inches across
from E to A. Though both shell and volute
are reduced to suit the size of these pages, the
relative proportions remain the same. It will
be noticed that the Chrysodomus antiquus
employed is a common specimen of a sinistral
shell, and has therefore produced the left-hand
volute of the capital. The right-hand volute
can be similarly produced from a common
right-handed whelk.
This method, though mechanically per-
formed, actually reproduces those proportions
of an Ionic volute which owe none of their
charm to mathematics ; and whether the
ancient Greeks used a shell or not in making
their designs, it is very significant that the
beauty of their workmanship should exhibit
so exact a harmony with the lines of an organic
growth that are nearly, but not quite, the
§>
^
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Ll
o
2
e
x.] PRINCIPLES OF BEAUTY 189
curves of a mathematical spiral. It is in this
subtle difference that their charm consists.
So strongly did Goodsir himself believe in
the correctness of the theory which Mr
Church is now developing on original and
progressive lines, that on his grave in
Edinburgh, where a medallion portrait is now
fixed, he originally ordered the logarithmic
spiral to be sculptured, which represented to
him the fundamental principle of beauty and
of growth in nature. Pettigrew and Francis
Darwin have done much towards the in-
vestigation of spiral formations in Nature;
and to many another besides Professor
Goodsir's pupil has the same idea appealed.
But not one of all of these has left such visible
monuments of insight and creative power as
the Leonardo who saw the same problems
both in Nature and in Art so long before them.
"Majestati Naturae Par Ingenium." We
have not yet said the last word on that theory
of flight he studied from the wings of birds
before the fifteenth century was gone. We
know very little more than he has written
of the mysterious forces which shape the
structures of waves, of reeds, of animals, of
shells. We are still groping after those
fundamental laws he sought, which existed
"before the fair flowers were seen, or ever
the movable powers were established, before
190 THE SHELL OF LEONARDO [chap. x.
the innumerable multitude of angels were
gathered together, or ever the heights of the
air were lifted up." We, too, must look
beyond, as he looked long ago towards the
stars, moving in the sky " to their own natural
home, which they enter unannounced as lords
that are certainly expected, and yet there is
a silent joy at their arrival."
<^
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g
INDEX
INDEX
Abbey of Thelema, 143
Accatabriga, 150
Accidents, 68
Africa, 48
Air tubes, 117
Airy's spirals, 130
Alaska, 48
Alaskan Bighorn, 81
Alberti (Leon Battista), 103
Aleutian Isles, 48
Amalekites, 37
Amboise, 146, 149, 152, 157, 159,
173
Ambrosian Library, 149
Ammonite, 42, 91, 93, 124, 126,
157
Amory valley, 48
Ampelopsis hederacea, 67
Amphidromus, 90
Amphidromus perversus, 89
Amsterdam, 47
Angora, 80
Antelopes, 79, 86
Antonio da Vinci, 150
Apennines, 22
Aphrodite, 180
Aploceras, 93
Arab, 48
Arbela, 36
Architecture, 8
Archimedes, 157
Arezzo, 108
Argali, 81
Argonauta Argo, 124
Arm supports, 87
Assyrian, 48
Asymmetry, 100
Atlas (Mount), 22
Augur-shell, 33
Auricula auris midae, 158
N
Australasia, 125
Azay le Kideau, 140
Baikal (Lake), 91
Balfour, (Henry), 47
Barbour (Professor), 60
Barrande, 93
Barton beds, 6, 173
Bayard, 147
Bean, 62, 66
Bedouin, 99
Belsay, 139
Belshazzar, 35
Beltrami, 11
Bengal, 45
Benjamin of Tudela, 111
Benjamites, 37
Berkshire, 65
Bernouilli, 24, 124, 180
Bighorn, 81
Billingsgate, 89
Blarney Castle, 139
Blois, 4, 9, 98, 145, 157, 162, 173
Blois (old staircase), 144
Blois (Chateau), 132, 141
Bologna, 110
Bonanno, 109
Bonnet, 55, 69, 72
Boreau, 150
Borneo, 46
Brachiopods, 86
Bramante, 151
Brantome, 143
Braun, 70
Brazil, 56
Bronze Age, 45
Browne (Sir Thomas), 19, 23,
37
Bryony, 67
Buccinum undatum, 89
193
194
INDEX
Buckland (Frank), 41
Buddhist, 48
Buffaloes, 86
Burke, 180
Bushbuck, 76
Byzantine, 48, 100, 106
Cesar Borgia, 147, 148
Calandrini, 70
CalcispongiaB, 52
Calderon (George), 49
Cambrensis (Giraldus), 34
Campanile of Pisa, 96, 108
Canterbury Cathedral, 30
Cape of Good Hope, 125
Capra falcon eri, 80
Capra walie, 83
Carnauba Palm, 56
Catharpin, 176
Catherine de Medici, 171
Celts, 36
Central column (origin), 135
Ceritheum giganteum, 119
Cerithium Portlandicum, 33
Ceropegia Gardnerii, 63
Cestracion philippi, 75
Chaldee, 35
Chambord, 143, 178
Chank shell, 44
Charles V., 134, 159
Charles VIII. , 159
Charlotte d'Albret, 148
Chartres, 97, 162
Chenonceaux, 140
Cher, 156
Chester, 153
Chesterfield, 96
Chestnut, 57
Chevreuil, 24
Chichly, 107
Chinon, 147
Chippendale, 113
Choanomphalus, 91
Chrysodomus antiquus, 90, 188
Church (A. H.), 70, 92, 124,
183
Clausilia laminata, 128
Clerk Maxwell, 183
Clifford (Professor), 21, 130
Climbing plants, 62
Clos-Luce, 48
Cloux, 147, 149
Clymenia, 92
Cobus unctuosus, 78
Cochlea, 75
Cochliodus contortus, 42
Codex Atlanticus, 11
Codice Atlantico, 149
Coffin screw, 32
Cokerell, 104
Collar-day, 36
College de Montaigu, 144
Coloration, 85
Columella muscle, 120
Columella plaits, 115
Columna flammea, 89
Convolvulus, 59, 62
Copenhagen, 96
Copernicia Cerifera, 56
Copernicus, 23
Corea, 125
Corkscrew, 31
Cormack McCarthy, 139
Cornish (Vaughan), 156
Cowry, 45
Crete, 45, 83
Crioceras bifurcatum, 91
Crypt of Canterbury, 31
Cumberland, 139
Curves in building, 104
Cuvier, 22, 74
Cyclamen, 55, 152
Cylindrella, 92
Cymbiola tuberculata, 120
Cymbium, 119, 167
Cypraea annulus, 45
Cypraea moneta, 45
Cypriot, 48
Cyrtoceras, 93
Dacca 44
Dacre Castle, 139
Daemonelix, 60
D'Alembert, 24
Darius, 36
Darwin, 16, 22, 62, 65, 67, 68, 70,
118
Darwin (Francis), 62
Date Palm, 57
Deluge (Scriptural), 12, 22, 156
Devil, 46
Devil's Corkscrews, 60
Devonshire, 55
Dexiotropic, 87
INDEX
195
Dexiotropic Voluta, 177
Dextral helix, 27
Diatoms, 52
Domestication 85
Donaldson, 104
Douglas (the Black) 139
Dover, 35
Driving, 27
Druids, 36
Drummond (Dr), 60
Dunstan (Professor), 173
Duval, 11
Eclipse (racehorse), 127
Eglantine, 152
Egypt. 45, 48, 59, 99
Elands, 78
Elasmobranch, 42
Electricity, 75
Elephant, 41
Elgin (Lord), 104
Entasis, 104
Eocene, 173
Equiangular spiral, 122
Etienne de Loup, 148
Euclid, 113
Euglena oxyuris, 74
Euglena spirogyra, 74
Evans (Arthur), 45
Evelyn, 108
Evolution, 70
Eyestone, 126
Felixstowe, 51
Fencing, 27, 38
Fiesole, 95, 160
Flanders, 141
Fletcher, MrB.R, 187
Flight of birds, 153
Floral diagrams, 59
Florence, 109
Florence Court, 60
Flying (Treatise on), 15
Fossil twisters, 60
Fra Giocondo, 156
Framlingham, 97
Francesco Sforza, 148
Francis 1, 109, 141, 143, 145, 147,
148, 150
Frankfort, 96
Freeman (Professor), 121
Fresnel. 130
Friston Tower, 140
Fusus antiquus, 51
Fyvie, 139
Galileo, 17
Garisenda, 110
Gaudry (Albert), 92
Gelnhausen, 96
Geymuller (Baron de), 151
Gideon, 37
Gilbert, 172
Gioconda (La), 156
Goats, 79
Goethe, 19, 70, 110
Goodsir (Professor), 124, 127,
180, 181, 189
Goodyear (Professor), 48, 101,
105, 106
Goniatites, 92
Gothic, 100, 101, 108
Gothic Eevival, 102
Goujon (Jean), 174
Govi, 11
Greeks, 48
Greek builders, 102
Gremsmuhlen, 129
Guglielmo, 109
Gulf of Guinea, 89
Gyroceras, 93
Hair, 39, 85
Haliotida Cunninghamii, 125
Haliotida gigantea, 125
Haliotida midse, 125
Hamilton (Sir W. R), 130
Hampshire, 173
Hand-rail, 141
Hand-writing, 13
Harpula fulminata, 120
Harvard, 184
Hay (D. B.), 180
Heart fibres, 75
Heart (valves of), 22
Helicoprion, 42
Helicteres ixora, 50
Hellenic art, 186
Helmholtz, 21
Helsingfors, 184
Hepplewhite, 113
Heredity, 70
Hertford College, 138
196
INDEX
Heteronymous, 78
Hexacoralla, 52
Highland Earn, 77, 81
Hindu, 44
Hofer, 105
Hogarth, 180
Holbein, 38
Holland, 141
Holmes (DrO. W.), 126
Holstein (Eastern), 129
Homonymous, 78
Honecort (Wilars de), 102
Honeysuckle, 62
Hops, 49, 62, 63, 65
Horse-chestnut, 57
House of Commons, 140
Houssaye (Arsene), 149
Humboldt, 17
Hume, 180
Hungary, 83
Hunter (William), 153
Huxley, 16
Ibex, 83
Iceland spar, 130
He de France, 101
II Moro, 147
Indre, 147
Infusoria, 125
Ionic Volute, 187
Ipswich, 140
Ireland, 139
Irish torques, 34
Irritability, 64
Isabella d'Este, 151
Isle of Bourbon, 57
Jaffna, 44
Japanese, 33
Jew's ear, 50
Jones (Inigo), 103
Joursanvault (Baron de), 173
Kepler, 4
Kew, 56
Kirchhoffer, 28, 38
Koninckina leonhardi, 87
Koodoo, 76
Kumatology, 156
Lady's Tresses, 55
Lamarck, 70
Lamona, 22
Lanistes, 51, 90
La Tremouille, 147
Leaning Tower, 109
Leda, 157
Lee-Metford, 32
Left-handedness, 37, 175
Left-handed writing, 175
Leiotropic, 32, 87
Lemstrom, 184
Leonardo da Vinci, 4, 10, 38, 114,
132, 145, 146, 150, 151
Lepus cuniculus, 158
Leslie (Sir John), 121, 125
Ley den, 47
Libri, 11
Limacina, 90
Lincolnshire, 140, 176
Lithuanian, 49
Lizards, 75
Loasa aurantiaca, 62
Loches, 147
Logarithmic curve, 92
Logarithmic spiral, 71, 122, 183,
184
Loire, 146, 149, 156
Lombardy, 24, 151, 160
London, 132, 153
Lotos, 47, 49
Louis XI., 148
Louis XII., 145, 148
Louvre, 134, 149
Ludovico Sforza, 147
Lyell, 22
Lyme Regis, 124
Lynn, 140
Macon, 149
Macroscaphites gigas, 92
Macroscaphites ivanii, 92
Madagascar, 57
Madrid, 143
Maison Carree, 105
Malay, 46, 47, 48
Malpighi, 117
Mammal, 75
Manderville (John de), 21
Manlius Torquatus, 36
Mansion House, 112
Manuscripts (Leonardo's), 13
Maori, 46
Marey (Professor), 154
INDEX
197
Marey (E. J.), 74
Marignano, 148
Markhor, 77, 84
Martello towers, 139
Medinet Habou, 104, 105
Mediterranean, 89
Meladromus, 90
Melanesia, 46
Melia, 93
Melzi (Francesco), 148, 149
Merignac, 38
Merino Ram, 81
Metamorphosis of leaves, 70
Meyer (Hermann), 75
Michelet, 19
Middleton Tower, 140
Milan, 108, 148, 173
Milan, Duke of, 151
Milanesi, 150
Minos, 45
Miratesta, 89
Mitra papalis, 27, 97
Mohammedan, 48
Mona Lisa, 169
Montreal, 60
Montrichard, 157
Moore (Julian), 101, 107
Moore (J. E. &), 52
Moorish, 99
Morantin, 149
Moseley (Canon), 122, 127, 180
Miintz, 11
Miiller ( Johann), 17
Muller-Walde, 11
Mycenae, 47
Nautiloceras, 93
Nautilus, 91, 92, 111,
123, 125, 126, 183
Naples, 36
Narwhals, 39
Nature (finite), 18
Nebulae (spiral), 76
Neottia spiralis, 55
Nepenthes, 117
Newel, 136
New Guinea, 46
Newton, 71, 181
New Zealand, 58
Nicobar Islands}to57
Nile, 48
Niobrara River, 60
115, 122,
Norfolk, 140
North Berwick, 139
North Sea, 51
Northumberland, 139
Nunney Castle, 140
Nutation, 63
Nyassa, 51
Oblique plans, 106
Oncyloceras spinigerum, 91
Onion, 59
Open staircase, 166
Operculum, 90, 122, 126
Ophidioceras, 93
Optically neutral, 131
Orchid, 55
Orientals, 34
Orthoceras, 93
Orton Scar, 35
Ovis nivicola, 86
Owen, 91
Oxford, 113, 138
Pacioli (Fra Luca), 13
Palaeolithic, 37
Palais de Justice, 96
Palazzo Contarini, 95, 136
Palissy (Bernard), 22
Pamir, 81
Pandanus millore, 57
Pandanus sylvestris, 57
Pandanus utilis, 57
Pandanus vandermeschii, 57
Paris, 113, 144
Parthenon, 100, 104, 105, 106
Pascal, 24
Passion flower, 62
Pasteur, 131
Patterns, 47
Pa via, 151
Peas, 62
Peels (Border), 139
Pelseneer, 90
Pennethorne, 104, 105
Penrose, 106
Penrose (F. C), 105
Persians, 35
Peru, 46
Petersburg, 42
Pettigrew, 75
Pharaoh's serpents, 41, 88
Phoenix dactylifera, 57
198
INDEX
Phryganeida, 74
Phyllotaxis, 69, 183, 184
Physa fontinalis, 89
Physa heterostropha, 89
Piedmont, 160
Piero da Vinci, 150
Pine Ridge, 61
Pinus smithiana, 55
Pir Panjal, 80
Pisa, 96, 108, 109
Pisa Baptistery, 110
Pisa Campanile, 111
Pisa Cathedral, 110
Piumati, 11
Plaits on columella,' 118
Planorbis, 90
Plants, 54
Pliny, 21
Plowman (A. B.), 184
Po (river), 22
Polarised light, 130
Pompeii, 36, 137
Pompholyx, 91
Portland screw, 33
Poulton (Professor), 85
Praxiteles, 180
Prat, 107
Prentice's Pillar, 29, 96, 144
Pritchard (Eric), 74
Quadruple helix, 163
Queen's Club, 176
Rabbits, 41, 62
Rabelais, 143
Ralph, Lord Cromwell, 140
Rata, 57
Ravaisson-Mollien, 11
Ravenna, 110,
Raymond du Temple, 135
Red Crag Sea, 51
Renaissance, 102, 108-
Revett, 104
Revival (Gothic), 102
Richter, 11, 150
Rocky Mountains, 31, 61
Rodin, 20
Roman screws, 137
Rome, 47
Romorantin, 151
Rosse (Lord), 76, 182
Rosslyn, 29
Rouen, 96, 106
Rundthor, 96
Ruskin, 16, 111, 121
Sabachnikoff, 11, 155
Sabba da Castiglione, 151
Sabella, 74
Sabella unispira, 74
Saint-Bel (M. Vial), 127
San Domenico, 95
San Paternian, 95
Sankho, 43
Saone, 149
Santa Maria della Grazie, 151
Sant' Ambrogio, 108
Sauldre, 149
Scala del Bovolo, 6, 95, 96
Scala della conchiglia, 6, 95
Scalaria scalaris, 6, 95, 123
Schaubert, 105
Schimper, 70
Schliemann, 43, 47
Scotland, 139
Screw-like flight, 154
Screw-palm, 57
Screws, 32
Screwstone, 33
Sea-bean, 126
Seailles, 11
Septuagint, 35
Shark's egg, 75
Shark's intestine, 158
Shavings, 33
Shell growth, 87
Shells, 50
Shells (carved), 170
Sheraton, 113
Siliquaria, 91
Simroth, 90
Sinistral helix, 28
Sinistral shells, 51, 89
Sinistral spiral, 174
Sinistral spiral (fourfold), 178
Sinistral spirals (interlacing),
178
Siphuncle, 91
Situtunga, 84
Skate, 42
Smilax aspera, 66
Smoke spirals, 152
Solarium maximum, 6, 94
Somersetshire, 140
INDEX
199
Spencer (Herbert), 74
Spiral curve, 78
Spiral formations, 26
Spiral forms of water, 156
Spiral horns, 76
Spiral nebulae, 76
Spiral staircase (origin), 132
Spiral Theory, 69
Spiral tubes, 116
Spiral twist, 78
Spira mirabilis, 124
Spirialis, 90
Spirifer mucronatus, 87
Spirostomum ambiguum, 73
Stein, 73, 125
Stentor coeruleus, 73, 125
Stent or igneus, 73
Stentor multiformis, 74
Stentor polymorphus, 73
Stentor Roeselii, 73
Stephanoceratidae, 91
St Florentin, 149
St Germain-en-Laye, 150
St John the Baptist, 149
St Mark's, 108
Stone Age, 46
St Ouen, 106
St Paul's, 107
Strassburg, 110
Streets, 113
Stuart, 104
Style, 53
Sulieman markhor, 84
Sweden, 47
Symmetrophobia, 109
Tanganyika, 51
Tantallon Castle, 139
Tasso, 179
Taste, 186
Tattershall Castle, 140
Taurotragus oryx, 78
Teeth, 42
Telescopium, 91, 160
Telescopium telescopium, 98,
119, 161
Tendrils, 66
Terebra maculata, 33
Terebra semiplicata, 33
Thebes, 104
Torques, 34
Torsion, 65, 68
Touraine, 143, 161
Tours, 97,157
Tower of London, 136
Tracheae, 116
Tragelaphus angasi, 79
Tragelaphus spekei, 84
Travancore, 43, 164
Trochus, 127
Troy, 43
Turbinella fusus, 120
Turbinella pirum, 44, 119
Turbinella rapa, 44
Turbine shells, 122
Turbo marmoratus, 126 *
Turbonilla, 91
Turbo olearius, 127
Turf (English), 128
Turner (Sir William), 127
Turritella, 160
Turrilites catenulatus, 89
Turrilites costatus, 89
Turritella lentiginosa, 119, 158,
162
Tuscany, 160
Tuticorin, 44
Two-fifth spiral, 69
Ultra-dextral, 90
Ultra-sinistral, 91
Uniform growth, 71
Uzielli, 11
Vasari, 109, 150
Venice, 108, 111, 160, 162
Venturi, 11
Victoria Nyanza, 51
Vienne, 147
Viollet le Due, 136, 142, 144
Vishnu, 43
Vitruvius, 102, 104
Voluta (dexiotropic), 177
Voluta musica, 120, 162
Voluta pacifica, 119
Voluta scalaris, 6
Voluta solandri, 119
Voluta vespertilio, 5, 89, 119,
162, 164, 167, 173
Volute, Ionic, 187
Von Mohl, 70
Von Thering, 90
Vorticella, 74
200
INDEX
Walking-sticks, 34
Wallachian sheep, 83
Wantage, 107
Ward (Rowland), 84
Washington, 36, 47
Waterbuck, 78
Water-lily, 58
Wax palm, 56
Weldon (Professor), 128
Westminster Abbey, 49, 107
Whelk, 90, 187
Wherry (Dr), 40, 64, 67, 76, 86
Whistler, 8
White River, 60
Wilkins, 104
William of Waynflete, 140
Wilson (Sir Daniel), 37
Winchester (Bishop of), 140
Winckelmann, 180
Windsor, 155
Withershins, 176
Wren, 108
Wren (Sir Christopher), 107
Wyndham (Rt. Hon. Geo.), 20
Yakoots, 48
Yew, 59
Zeuglodon, 75
Zulus, 34
Zygospira modesta, 87
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SMITHSONIAN INSTITUTION LIBRARIES
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